Loading...
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Local APIC handling, local APIC timers
4 *
5 * (c) 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
6 *
7 * Fixes
8 * Maciej W. Rozycki : Bits for genuine 82489DX APICs;
9 * thanks to Eric Gilmore
10 * and Rolf G. Tews
11 * for testing these extensively.
12 * Maciej W. Rozycki : Various updates and fixes.
13 * Mikael Pettersson : Power Management for UP-APIC.
14 * Pavel Machek and
15 * Mikael Pettersson : PM converted to driver model.
16 */
17
18#include <linux/perf_event.h>
19#include <linux/kernel_stat.h>
20#include <linux/mc146818rtc.h>
21#include <linux/acpi_pmtmr.h>
22#include <linux/clockchips.h>
23#include <linux/interrupt.h>
24#include <linux/memblock.h>
25#include <linux/ftrace.h>
26#include <linux/ioport.h>
27#include <linux/export.h>
28#include <linux/syscore_ops.h>
29#include <linux/delay.h>
30#include <linux/timex.h>
31#include <linux/i8253.h>
32#include <linux/dmar.h>
33#include <linux/init.h>
34#include <linux/cpu.h>
35#include <linux/dmi.h>
36#include <linux/smp.h>
37#include <linux/mm.h>
38
39#include <asm/trace/irq_vectors.h>
40#include <asm/irq_remapping.h>
41#include <asm/perf_event.h>
42#include <asm/x86_init.h>
43#include <asm/pgalloc.h>
44#include <linux/atomic.h>
45#include <asm/mpspec.h>
46#include <asm/i8259.h>
47#include <asm/proto.h>
48#include <asm/traps.h>
49#include <asm/apic.h>
50#include <asm/io_apic.h>
51#include <asm/desc.h>
52#include <asm/hpet.h>
53#include <asm/mtrr.h>
54#include <asm/time.h>
55#include <asm/smp.h>
56#include <asm/mce.h>
57#include <asm/tsc.h>
58#include <asm/hypervisor.h>
59#include <asm/cpu_device_id.h>
60#include <asm/intel-family.h>
61#include <asm/irq_regs.h>
62
63unsigned int num_processors;
64
65unsigned disabled_cpus;
66
67/* Processor that is doing the boot up */
68unsigned int boot_cpu_physical_apicid __ro_after_init = -1U;
69EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid);
70
71u8 boot_cpu_apic_version __ro_after_init;
72
73/*
74 * The highest APIC ID seen during enumeration.
75 */
76static unsigned int max_physical_apicid;
77
78/*
79 * Bitmask of physically existing CPUs:
80 */
81physid_mask_t phys_cpu_present_map;
82
83/*
84 * Processor to be disabled specified by kernel parameter
85 * disable_cpu_apicid=<int>, mostly used for the kdump 2nd kernel to
86 * avoid undefined behaviour caused by sending INIT from AP to BSP.
87 */
88static unsigned int disabled_cpu_apicid __ro_after_init = BAD_APICID;
89
90/*
91 * This variable controls which CPUs receive external NMIs. By default,
92 * external NMIs are delivered only to the BSP.
93 */
94static int apic_extnmi __ro_after_init = APIC_EXTNMI_BSP;
95
96/*
97 * Map cpu index to physical APIC ID
98 */
99DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid, BAD_APICID);
100DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid, BAD_APICID);
101DEFINE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_acpiid, U32_MAX);
102EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
103EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
104EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_acpiid);
105
106#ifdef CONFIG_X86_32
107
108/*
109 * On x86_32, the mapping between cpu and logical apicid may vary
110 * depending on apic in use. The following early percpu variable is
111 * used for the mapping. This is where the behaviors of x86_64 and 32
112 * actually diverge. Let's keep it ugly for now.
113 */
114DEFINE_EARLY_PER_CPU_READ_MOSTLY(int, x86_cpu_to_logical_apicid, BAD_APICID);
115
116/* Local APIC was disabled by the BIOS and enabled by the kernel */
117static int enabled_via_apicbase __ro_after_init;
118
119/*
120 * Handle interrupt mode configuration register (IMCR).
121 * This register controls whether the interrupt signals
122 * that reach the BSP come from the master PIC or from the
123 * local APIC. Before entering Symmetric I/O Mode, either
124 * the BIOS or the operating system must switch out of
125 * PIC Mode by changing the IMCR.
126 */
127static inline void imcr_pic_to_apic(void)
128{
129 /* select IMCR register */
130 outb(0x70, 0x22);
131 /* NMI and 8259 INTR go through APIC */
132 outb(0x01, 0x23);
133}
134
135static inline void imcr_apic_to_pic(void)
136{
137 /* select IMCR register */
138 outb(0x70, 0x22);
139 /* NMI and 8259 INTR go directly to BSP */
140 outb(0x00, 0x23);
141}
142#endif
143
144/*
145 * Knob to control our willingness to enable the local APIC.
146 *
147 * +1=force-enable
148 */
149static int force_enable_local_apic __initdata;
150
151/*
152 * APIC command line parameters
153 */
154static int __init parse_lapic(char *arg)
155{
156 if (IS_ENABLED(CONFIG_X86_32) && !arg)
157 force_enable_local_apic = 1;
158 else if (arg && !strncmp(arg, "notscdeadline", 13))
159 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
160 return 0;
161}
162early_param("lapic", parse_lapic);
163
164#ifdef CONFIG_X86_64
165static int apic_calibrate_pmtmr __initdata;
166static __init int setup_apicpmtimer(char *s)
167{
168 apic_calibrate_pmtmr = 1;
169 notsc_setup(NULL);
170 return 0;
171}
172__setup("apicpmtimer", setup_apicpmtimer);
173#endif
174
175unsigned long mp_lapic_addr __ro_after_init;
176int disable_apic __ro_after_init;
177/* Disable local APIC timer from the kernel commandline or via dmi quirk */
178static int disable_apic_timer __initdata;
179/* Local APIC timer works in C2 */
180int local_apic_timer_c2_ok __ro_after_init;
181EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
182
183/*
184 * Debug level, exported for io_apic.c
185 */
186int apic_verbosity __ro_after_init;
187
188int pic_mode __ro_after_init;
189
190/* Have we found an MP table */
191int smp_found_config __ro_after_init;
192
193static struct resource lapic_resource = {
194 .name = "Local APIC",
195 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
196};
197
198unsigned int lapic_timer_period = 0;
199
200static void apic_pm_activate(void);
201
202static unsigned long apic_phys __ro_after_init;
203
204/*
205 * Get the LAPIC version
206 */
207static inline int lapic_get_version(void)
208{
209 return GET_APIC_VERSION(apic_read(APIC_LVR));
210}
211
212/*
213 * Check, if the APIC is integrated or a separate chip
214 */
215static inline int lapic_is_integrated(void)
216{
217 return APIC_INTEGRATED(lapic_get_version());
218}
219
220/*
221 * Check, whether this is a modern or a first generation APIC
222 */
223static int modern_apic(void)
224{
225 /* AMD systems use old APIC versions, so check the CPU */
226 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
227 boot_cpu_data.x86 >= 0xf)
228 return 1;
229
230 /* Hygon systems use modern APIC */
231 if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
232 return 1;
233
234 return lapic_get_version() >= 0x14;
235}
236
237/*
238 * right after this call apic become NOOP driven
239 * so apic->write/read doesn't do anything
240 */
241static void __init apic_disable(void)
242{
243 pr_info("APIC: switched to apic NOOP\n");
244 apic = &apic_noop;
245}
246
247void native_apic_wait_icr_idle(void)
248{
249 while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
250 cpu_relax();
251}
252
253u32 native_safe_apic_wait_icr_idle(void)
254{
255 u32 send_status;
256 int timeout;
257
258 timeout = 0;
259 do {
260 send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
261 if (!send_status)
262 break;
263 inc_irq_stat(icr_read_retry_count);
264 udelay(100);
265 } while (timeout++ < 1000);
266
267 return send_status;
268}
269
270void native_apic_icr_write(u32 low, u32 id)
271{
272 unsigned long flags;
273
274 local_irq_save(flags);
275 apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
276 apic_write(APIC_ICR, low);
277 local_irq_restore(flags);
278}
279
280u64 native_apic_icr_read(void)
281{
282 u32 icr1, icr2;
283
284 icr2 = apic_read(APIC_ICR2);
285 icr1 = apic_read(APIC_ICR);
286
287 return icr1 | ((u64)icr2 << 32);
288}
289
290#ifdef CONFIG_X86_32
291/**
292 * get_physical_broadcast - Get number of physical broadcast IDs
293 */
294int get_physical_broadcast(void)
295{
296 return modern_apic() ? 0xff : 0xf;
297}
298#endif
299
300/**
301 * lapic_get_maxlvt - get the maximum number of local vector table entries
302 */
303int lapic_get_maxlvt(void)
304{
305 /*
306 * - we always have APIC integrated on 64bit mode
307 * - 82489DXs do not report # of LVT entries
308 */
309 return lapic_is_integrated() ? GET_APIC_MAXLVT(apic_read(APIC_LVR)) : 2;
310}
311
312/*
313 * Local APIC timer
314 */
315
316/* Clock divisor */
317#define APIC_DIVISOR 16
318#define TSC_DIVISOR 8
319
320/*
321 * This function sets up the local APIC timer, with a timeout of
322 * 'clocks' APIC bus clock. During calibration we actually call
323 * this function twice on the boot CPU, once with a bogus timeout
324 * value, second time for real. The other (noncalibrating) CPUs
325 * call this function only once, with the real, calibrated value.
326 *
327 * We do reads before writes even if unnecessary, to get around the
328 * P5 APIC double write bug.
329 */
330static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
331{
332 unsigned int lvtt_value, tmp_value;
333
334 lvtt_value = LOCAL_TIMER_VECTOR;
335 if (!oneshot)
336 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
337 else if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
338 lvtt_value |= APIC_LVT_TIMER_TSCDEADLINE;
339
340 if (!lapic_is_integrated())
341 lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
342
343 if (!irqen)
344 lvtt_value |= APIC_LVT_MASKED;
345
346 apic_write(APIC_LVTT, lvtt_value);
347
348 if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) {
349 /*
350 * See Intel SDM: TSC-Deadline Mode chapter. In xAPIC mode,
351 * writing to the APIC LVTT and TSC_DEADLINE MSR isn't serialized.
352 * According to Intel, MFENCE can do the serialization here.
353 */
354 asm volatile("mfence" : : : "memory");
355
356 printk_once(KERN_DEBUG "TSC deadline timer enabled\n");
357 return;
358 }
359
360 /*
361 * Divide PICLK by 16
362 */
363 tmp_value = apic_read(APIC_TDCR);
364 apic_write(APIC_TDCR,
365 (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
366 APIC_TDR_DIV_16);
367
368 if (!oneshot)
369 apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
370}
371
372/*
373 * Setup extended LVT, AMD specific
374 *
375 * Software should use the LVT offsets the BIOS provides. The offsets
376 * are determined by the subsystems using it like those for MCE
377 * threshold or IBS. On K8 only offset 0 (APIC500) and MCE interrupts
378 * are supported. Beginning with family 10h at least 4 offsets are
379 * available.
380 *
381 * Since the offsets must be consistent for all cores, we keep track
382 * of the LVT offsets in software and reserve the offset for the same
383 * vector also to be used on other cores. An offset is freed by
384 * setting the entry to APIC_EILVT_MASKED.
385 *
386 * If the BIOS is right, there should be no conflicts. Otherwise a
387 * "[Firmware Bug]: ..." error message is generated. However, if
388 * software does not properly determines the offsets, it is not
389 * necessarily a BIOS bug.
390 */
391
392static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX];
393
394static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new)
395{
396 return (old & APIC_EILVT_MASKED)
397 || (new == APIC_EILVT_MASKED)
398 || ((new & ~APIC_EILVT_MASKED) == old);
399}
400
401static unsigned int reserve_eilvt_offset(int offset, unsigned int new)
402{
403 unsigned int rsvd, vector;
404
405 if (offset >= APIC_EILVT_NR_MAX)
406 return ~0;
407
408 rsvd = atomic_read(&eilvt_offsets[offset]);
409 do {
410 vector = rsvd & ~APIC_EILVT_MASKED; /* 0: unassigned */
411 if (vector && !eilvt_entry_is_changeable(vector, new))
412 /* may not change if vectors are different */
413 return rsvd;
414 rsvd = atomic_cmpxchg(&eilvt_offsets[offset], rsvd, new);
415 } while (rsvd != new);
416
417 rsvd &= ~APIC_EILVT_MASKED;
418 if (rsvd && rsvd != vector)
419 pr_info("LVT offset %d assigned for vector 0x%02x\n",
420 offset, rsvd);
421
422 return new;
423}
424
425/*
426 * If mask=1, the LVT entry does not generate interrupts while mask=0
427 * enables the vector. See also the BKDGs. Must be called with
428 * preemption disabled.
429 */
430
431int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask)
432{
433 unsigned long reg = APIC_EILVTn(offset);
434 unsigned int new, old, reserved;
435
436 new = (mask << 16) | (msg_type << 8) | vector;
437 old = apic_read(reg);
438 reserved = reserve_eilvt_offset(offset, new);
439
440 if (reserved != new) {
441 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
442 "vector 0x%x, but the register is already in use for "
443 "vector 0x%x on another cpu\n",
444 smp_processor_id(), reg, offset, new, reserved);
445 return -EINVAL;
446 }
447
448 if (!eilvt_entry_is_changeable(old, new)) {
449 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
450 "vector 0x%x, but the register is already in use for "
451 "vector 0x%x on this cpu\n",
452 smp_processor_id(), reg, offset, new, old);
453 return -EBUSY;
454 }
455
456 apic_write(reg, new);
457
458 return 0;
459}
460EXPORT_SYMBOL_GPL(setup_APIC_eilvt);
461
462/*
463 * Program the next event, relative to now
464 */
465static int lapic_next_event(unsigned long delta,
466 struct clock_event_device *evt)
467{
468 apic_write(APIC_TMICT, delta);
469 return 0;
470}
471
472static int lapic_next_deadline(unsigned long delta,
473 struct clock_event_device *evt)
474{
475 u64 tsc;
476
477 tsc = rdtsc();
478 wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR));
479 return 0;
480}
481
482static int lapic_timer_shutdown(struct clock_event_device *evt)
483{
484 unsigned int v;
485
486 /* Lapic used as dummy for broadcast ? */
487 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
488 return 0;
489
490 v = apic_read(APIC_LVTT);
491 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
492 apic_write(APIC_LVTT, v);
493 apic_write(APIC_TMICT, 0);
494 return 0;
495}
496
497static inline int
498lapic_timer_set_periodic_oneshot(struct clock_event_device *evt, bool oneshot)
499{
500 /* Lapic used as dummy for broadcast ? */
501 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
502 return 0;
503
504 __setup_APIC_LVTT(lapic_timer_period, oneshot, 1);
505 return 0;
506}
507
508static int lapic_timer_set_periodic(struct clock_event_device *evt)
509{
510 return lapic_timer_set_periodic_oneshot(evt, false);
511}
512
513static int lapic_timer_set_oneshot(struct clock_event_device *evt)
514{
515 return lapic_timer_set_periodic_oneshot(evt, true);
516}
517
518/*
519 * Local APIC timer broadcast function
520 */
521static void lapic_timer_broadcast(const struct cpumask *mask)
522{
523#ifdef CONFIG_SMP
524 apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
525#endif
526}
527
528
529/*
530 * The local apic timer can be used for any function which is CPU local.
531 */
532static struct clock_event_device lapic_clockevent = {
533 .name = "lapic",
534 .features = CLOCK_EVT_FEAT_PERIODIC |
535 CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP
536 | CLOCK_EVT_FEAT_DUMMY,
537 .shift = 32,
538 .set_state_shutdown = lapic_timer_shutdown,
539 .set_state_periodic = lapic_timer_set_periodic,
540 .set_state_oneshot = lapic_timer_set_oneshot,
541 .set_state_oneshot_stopped = lapic_timer_shutdown,
542 .set_next_event = lapic_next_event,
543 .broadcast = lapic_timer_broadcast,
544 .rating = 100,
545 .irq = -1,
546};
547static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
548
549#define DEADLINE_MODEL_MATCH_FUNC(model, func) \
550 { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long)&func }
551
552#define DEADLINE_MODEL_MATCH_REV(model, rev) \
553 { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long)rev }
554
555static u32 hsx_deadline_rev(void)
556{
557 switch (boot_cpu_data.x86_stepping) {
558 case 0x02: return 0x3a; /* EP */
559 case 0x04: return 0x0f; /* EX */
560 }
561
562 return ~0U;
563}
564
565static u32 bdx_deadline_rev(void)
566{
567 switch (boot_cpu_data.x86_stepping) {
568 case 0x02: return 0x00000011;
569 case 0x03: return 0x0700000e;
570 case 0x04: return 0x0f00000c;
571 case 0x05: return 0x0e000003;
572 }
573
574 return ~0U;
575}
576
577static u32 skx_deadline_rev(void)
578{
579 switch (boot_cpu_data.x86_stepping) {
580 case 0x03: return 0x01000136;
581 case 0x04: return 0x02000014;
582 }
583
584 if (boot_cpu_data.x86_stepping > 4)
585 return 0;
586
587 return ~0U;
588}
589
590static const struct x86_cpu_id deadline_match[] = {
591 DEADLINE_MODEL_MATCH_FUNC( INTEL_FAM6_HASWELL_X, hsx_deadline_rev),
592 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL_X, 0x0b000020),
593 DEADLINE_MODEL_MATCH_FUNC( INTEL_FAM6_BROADWELL_D, bdx_deadline_rev),
594 DEADLINE_MODEL_MATCH_FUNC( INTEL_FAM6_SKYLAKE_X, skx_deadline_rev),
595
596 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL, 0x22),
597 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL_L, 0x20),
598 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL_G, 0x17),
599
600 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL, 0x25),
601 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL_G, 0x17),
602
603 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_SKYLAKE_L, 0xb2),
604 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_SKYLAKE, 0xb2),
605
606 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_KABYLAKE_L, 0x52),
607 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_KABYLAKE, 0x52),
608
609 {},
610};
611
612static void apic_check_deadline_errata(void)
613{
614 const struct x86_cpu_id *m;
615 u32 rev;
616
617 if (!boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER) ||
618 boot_cpu_has(X86_FEATURE_HYPERVISOR))
619 return;
620
621 m = x86_match_cpu(deadline_match);
622 if (!m)
623 return;
624
625 /*
626 * Function pointers will have the MSB set due to address layout,
627 * immediate revisions will not.
628 */
629 if ((long)m->driver_data < 0)
630 rev = ((u32 (*)(void))(m->driver_data))();
631 else
632 rev = (u32)m->driver_data;
633
634 if (boot_cpu_data.microcode >= rev)
635 return;
636
637 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
638 pr_err(FW_BUG "TSC_DEADLINE disabled due to Errata; "
639 "please update microcode to version: 0x%x (or later)\n", rev);
640}
641
642/*
643 * Setup the local APIC timer for this CPU. Copy the initialized values
644 * of the boot CPU and register the clock event in the framework.
645 */
646static void setup_APIC_timer(void)
647{
648 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
649
650 if (this_cpu_has(X86_FEATURE_ARAT)) {
651 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP;
652 /* Make LAPIC timer preferrable over percpu HPET */
653 lapic_clockevent.rating = 150;
654 }
655
656 memcpy(levt, &lapic_clockevent, sizeof(*levt));
657 levt->cpumask = cpumask_of(smp_processor_id());
658
659 if (this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) {
660 levt->name = "lapic-deadline";
661 levt->features &= ~(CLOCK_EVT_FEAT_PERIODIC |
662 CLOCK_EVT_FEAT_DUMMY);
663 levt->set_next_event = lapic_next_deadline;
664 clockevents_config_and_register(levt,
665 tsc_khz * (1000 / TSC_DIVISOR),
666 0xF, ~0UL);
667 } else
668 clockevents_register_device(levt);
669}
670
671/*
672 * Install the updated TSC frequency from recalibration at the TSC
673 * deadline clockevent devices.
674 */
675static void __lapic_update_tsc_freq(void *info)
676{
677 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
678
679 if (!this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
680 return;
681
682 clockevents_update_freq(levt, tsc_khz * (1000 / TSC_DIVISOR));
683}
684
685void lapic_update_tsc_freq(void)
686{
687 /*
688 * The clockevent device's ->mult and ->shift can both be
689 * changed. In order to avoid races, schedule the frequency
690 * update code on each CPU.
691 */
692 on_each_cpu(__lapic_update_tsc_freq, NULL, 0);
693}
694
695/*
696 * In this functions we calibrate APIC bus clocks to the external timer.
697 *
698 * We want to do the calibration only once since we want to have local timer
699 * irqs syncron. CPUs connected by the same APIC bus have the very same bus
700 * frequency.
701 *
702 * This was previously done by reading the PIT/HPET and waiting for a wrap
703 * around to find out, that a tick has elapsed. I have a box, where the PIT
704 * readout is broken, so it never gets out of the wait loop again. This was
705 * also reported by others.
706 *
707 * Monitoring the jiffies value is inaccurate and the clockevents
708 * infrastructure allows us to do a simple substitution of the interrupt
709 * handler.
710 *
711 * The calibration routine also uses the pm_timer when possible, as the PIT
712 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
713 * back to normal later in the boot process).
714 */
715
716#define LAPIC_CAL_LOOPS (HZ/10)
717
718static __initdata int lapic_cal_loops = -1;
719static __initdata long lapic_cal_t1, lapic_cal_t2;
720static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
721static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
722static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
723
724/*
725 * Temporary interrupt handler and polled calibration function.
726 */
727static void __init lapic_cal_handler(struct clock_event_device *dev)
728{
729 unsigned long long tsc = 0;
730 long tapic = apic_read(APIC_TMCCT);
731 unsigned long pm = acpi_pm_read_early();
732
733 if (boot_cpu_has(X86_FEATURE_TSC))
734 tsc = rdtsc();
735
736 switch (lapic_cal_loops++) {
737 case 0:
738 lapic_cal_t1 = tapic;
739 lapic_cal_tsc1 = tsc;
740 lapic_cal_pm1 = pm;
741 lapic_cal_j1 = jiffies;
742 break;
743
744 case LAPIC_CAL_LOOPS:
745 lapic_cal_t2 = tapic;
746 lapic_cal_tsc2 = tsc;
747 if (pm < lapic_cal_pm1)
748 pm += ACPI_PM_OVRRUN;
749 lapic_cal_pm2 = pm;
750 lapic_cal_j2 = jiffies;
751 break;
752 }
753}
754
755static int __init
756calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc)
757{
758 const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
759 const long pm_thresh = pm_100ms / 100;
760 unsigned long mult;
761 u64 res;
762
763#ifndef CONFIG_X86_PM_TIMER
764 return -1;
765#endif
766
767 apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm);
768
769 /* Check, if the PM timer is available */
770 if (!deltapm)
771 return -1;
772
773 mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
774
775 if (deltapm > (pm_100ms - pm_thresh) &&
776 deltapm < (pm_100ms + pm_thresh)) {
777 apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n");
778 return 0;
779 }
780
781 res = (((u64)deltapm) * mult) >> 22;
782 do_div(res, 1000000);
783 pr_warning("APIC calibration not consistent "
784 "with PM-Timer: %ldms instead of 100ms\n",(long)res);
785
786 /* Correct the lapic counter value */
787 res = (((u64)(*delta)) * pm_100ms);
788 do_div(res, deltapm);
789 pr_info("APIC delta adjusted to PM-Timer: "
790 "%lu (%ld)\n", (unsigned long)res, *delta);
791 *delta = (long)res;
792
793 /* Correct the tsc counter value */
794 if (boot_cpu_has(X86_FEATURE_TSC)) {
795 res = (((u64)(*deltatsc)) * pm_100ms);
796 do_div(res, deltapm);
797 apic_printk(APIC_VERBOSE, "TSC delta adjusted to "
798 "PM-Timer: %lu (%ld)\n",
799 (unsigned long)res, *deltatsc);
800 *deltatsc = (long)res;
801 }
802
803 return 0;
804}
805
806static int __init lapic_init_clockevent(void)
807{
808 if (!lapic_timer_period)
809 return -1;
810
811 /* Calculate the scaled math multiplication factor */
812 lapic_clockevent.mult = div_sc(lapic_timer_period/APIC_DIVISOR,
813 TICK_NSEC, lapic_clockevent.shift);
814 lapic_clockevent.max_delta_ns =
815 clockevent_delta2ns(0x7FFFFFFF, &lapic_clockevent);
816 lapic_clockevent.max_delta_ticks = 0x7FFFFFFF;
817 lapic_clockevent.min_delta_ns =
818 clockevent_delta2ns(0xF, &lapic_clockevent);
819 lapic_clockevent.min_delta_ticks = 0xF;
820
821 return 0;
822}
823
824bool __init apic_needs_pit(void)
825{
826 /*
827 * If the frequencies are not known, PIT is required for both TSC
828 * and apic timer calibration.
829 */
830 if (!tsc_khz || !cpu_khz)
831 return true;
832
833 /* Is there an APIC at all? */
834 if (!boot_cpu_has(X86_FEATURE_APIC))
835 return true;
836
837 /* Virt guests may lack ARAT, but still have DEADLINE */
838 if (!boot_cpu_has(X86_FEATURE_ARAT))
839 return true;
840
841 /* Deadline timer is based on TSC so no further PIT action required */
842 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
843 return false;
844
845 /* APIC timer disabled? */
846 if (disable_apic_timer)
847 return true;
848 /*
849 * The APIC timer frequency is known already, no PIT calibration
850 * required. If unknown, let the PIT be initialized.
851 */
852 return lapic_timer_period == 0;
853}
854
855static int __init calibrate_APIC_clock(void)
856{
857 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
858 u64 tsc_perj = 0, tsc_start = 0;
859 unsigned long jif_start;
860 unsigned long deltaj;
861 long delta, deltatsc;
862 int pm_referenced = 0;
863
864 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
865 return 0;
866
867 /*
868 * Check if lapic timer has already been calibrated by platform
869 * specific routine, such as tsc calibration code. If so just fill
870 * in the clockevent structure and return.
871 */
872 if (!lapic_init_clockevent()) {
873 apic_printk(APIC_VERBOSE, "lapic timer already calibrated %d\n",
874 lapic_timer_period);
875 /*
876 * Direct calibration methods must have an always running
877 * local APIC timer, no need for broadcast timer.
878 */
879 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
880 return 0;
881 }
882
883 apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
884 "calibrating APIC timer ...\n");
885
886 /*
887 * There are platforms w/o global clockevent devices. Instead of
888 * making the calibration conditional on that, use a polling based
889 * approach everywhere.
890 */
891 local_irq_disable();
892
893 /*
894 * Setup the APIC counter to maximum. There is no way the lapic
895 * can underflow in the 100ms detection time frame
896 */
897 __setup_APIC_LVTT(0xffffffff, 0, 0);
898
899 /*
900 * Methods to terminate the calibration loop:
901 * 1) Global clockevent if available (jiffies)
902 * 2) TSC if available and frequency is known
903 */
904 jif_start = READ_ONCE(jiffies);
905
906 if (tsc_khz) {
907 tsc_start = rdtsc();
908 tsc_perj = div_u64((u64)tsc_khz * 1000, HZ);
909 }
910
911 /*
912 * Enable interrupts so the tick can fire, if a global
913 * clockevent device is available
914 */
915 local_irq_enable();
916
917 while (lapic_cal_loops <= LAPIC_CAL_LOOPS) {
918 /* Wait for a tick to elapse */
919 while (1) {
920 if (tsc_khz) {
921 u64 tsc_now = rdtsc();
922 if ((tsc_now - tsc_start) >= tsc_perj) {
923 tsc_start += tsc_perj;
924 break;
925 }
926 } else {
927 unsigned long jif_now = READ_ONCE(jiffies);
928
929 if (time_after(jif_now, jif_start)) {
930 jif_start = jif_now;
931 break;
932 }
933 }
934 cpu_relax();
935 }
936
937 /* Invoke the calibration routine */
938 local_irq_disable();
939 lapic_cal_handler(NULL);
940 local_irq_enable();
941 }
942
943 local_irq_disable();
944
945 /* Build delta t1-t2 as apic timer counts down */
946 delta = lapic_cal_t1 - lapic_cal_t2;
947 apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
948
949 deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
950
951 /* we trust the PM based calibration if possible */
952 pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
953 &delta, &deltatsc);
954
955 lapic_timer_period = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
956 lapic_init_clockevent();
957
958 apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
959 apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult);
960 apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
961 lapic_timer_period);
962
963 if (boot_cpu_has(X86_FEATURE_TSC)) {
964 apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
965 "%ld.%04ld MHz.\n",
966 (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
967 (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
968 }
969
970 apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
971 "%u.%04u MHz.\n",
972 lapic_timer_period / (1000000 / HZ),
973 lapic_timer_period % (1000000 / HZ));
974
975 /*
976 * Do a sanity check on the APIC calibration result
977 */
978 if (lapic_timer_period < (1000000 / HZ)) {
979 local_irq_enable();
980 pr_warning("APIC frequency too slow, disabling apic timer\n");
981 return -1;
982 }
983
984 levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
985
986 /*
987 * PM timer calibration failed or not turned on so lets try APIC
988 * timer based calibration, if a global clockevent device is
989 * available.
990 */
991 if (!pm_referenced && global_clock_event) {
992 apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
993
994 /*
995 * Setup the apic timer manually
996 */
997 levt->event_handler = lapic_cal_handler;
998 lapic_timer_set_periodic(levt);
999 lapic_cal_loops = -1;
1000
1001 /* Let the interrupts run */
1002 local_irq_enable();
1003
1004 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
1005 cpu_relax();
1006
1007 /* Stop the lapic timer */
1008 local_irq_disable();
1009 lapic_timer_shutdown(levt);
1010
1011 /* Jiffies delta */
1012 deltaj = lapic_cal_j2 - lapic_cal_j1;
1013 apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
1014
1015 /* Check, if the jiffies result is consistent */
1016 if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
1017 apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
1018 else
1019 levt->features |= CLOCK_EVT_FEAT_DUMMY;
1020 }
1021 local_irq_enable();
1022
1023 if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
1024 pr_warning("APIC timer disabled due to verification failure\n");
1025 return -1;
1026 }
1027
1028 return 0;
1029}
1030
1031/*
1032 * Setup the boot APIC
1033 *
1034 * Calibrate and verify the result.
1035 */
1036void __init setup_boot_APIC_clock(void)
1037{
1038 /*
1039 * The local apic timer can be disabled via the kernel
1040 * commandline or from the CPU detection code. Register the lapic
1041 * timer as a dummy clock event source on SMP systems, so the
1042 * broadcast mechanism is used. On UP systems simply ignore it.
1043 */
1044 if (disable_apic_timer) {
1045 pr_info("Disabling APIC timer\n");
1046 /* No broadcast on UP ! */
1047 if (num_possible_cpus() > 1) {
1048 lapic_clockevent.mult = 1;
1049 setup_APIC_timer();
1050 }
1051 return;
1052 }
1053
1054 if (calibrate_APIC_clock()) {
1055 /* No broadcast on UP ! */
1056 if (num_possible_cpus() > 1)
1057 setup_APIC_timer();
1058 return;
1059 }
1060
1061 /*
1062 * If nmi_watchdog is set to IO_APIC, we need the
1063 * PIT/HPET going. Otherwise register lapic as a dummy
1064 * device.
1065 */
1066 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
1067
1068 /* Setup the lapic or request the broadcast */
1069 setup_APIC_timer();
1070 amd_e400_c1e_apic_setup();
1071}
1072
1073void setup_secondary_APIC_clock(void)
1074{
1075 setup_APIC_timer();
1076 amd_e400_c1e_apic_setup();
1077}
1078
1079/*
1080 * The guts of the apic timer interrupt
1081 */
1082static void local_apic_timer_interrupt(void)
1083{
1084 struct clock_event_device *evt = this_cpu_ptr(&lapic_events);
1085
1086 /*
1087 * Normally we should not be here till LAPIC has been initialized but
1088 * in some cases like kdump, its possible that there is a pending LAPIC
1089 * timer interrupt from previous kernel's context and is delivered in
1090 * new kernel the moment interrupts are enabled.
1091 *
1092 * Interrupts are enabled early and LAPIC is setup much later, hence
1093 * its possible that when we get here evt->event_handler is NULL.
1094 * Check for event_handler being NULL and discard the interrupt as
1095 * spurious.
1096 */
1097 if (!evt->event_handler) {
1098 pr_warning("Spurious LAPIC timer interrupt on cpu %d\n",
1099 smp_processor_id());
1100 /* Switch it off */
1101 lapic_timer_shutdown(evt);
1102 return;
1103 }
1104
1105 /*
1106 * the NMI deadlock-detector uses this.
1107 */
1108 inc_irq_stat(apic_timer_irqs);
1109
1110 evt->event_handler(evt);
1111}
1112
1113/*
1114 * Local APIC timer interrupt. This is the most natural way for doing
1115 * local interrupts, but local timer interrupts can be emulated by
1116 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
1117 *
1118 * [ if a single-CPU system runs an SMP kernel then we call the local
1119 * interrupt as well. Thus we cannot inline the local irq ... ]
1120 */
1121__visible void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs)
1122{
1123 struct pt_regs *old_regs = set_irq_regs(regs);
1124
1125 /*
1126 * NOTE! We'd better ACK the irq immediately,
1127 * because timer handling can be slow.
1128 *
1129 * update_process_times() expects us to have done irq_enter().
1130 * Besides, if we don't timer interrupts ignore the global
1131 * interrupt lock, which is the WrongThing (tm) to do.
1132 */
1133 entering_ack_irq();
1134 trace_local_timer_entry(LOCAL_TIMER_VECTOR);
1135 local_apic_timer_interrupt();
1136 trace_local_timer_exit(LOCAL_TIMER_VECTOR);
1137 exiting_irq();
1138
1139 set_irq_regs(old_regs);
1140}
1141
1142int setup_profiling_timer(unsigned int multiplier)
1143{
1144 return -EINVAL;
1145}
1146
1147/*
1148 * Local APIC start and shutdown
1149 */
1150
1151/**
1152 * clear_local_APIC - shutdown the local APIC
1153 *
1154 * This is called, when a CPU is disabled and before rebooting, so the state of
1155 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
1156 * leftovers during boot.
1157 */
1158void clear_local_APIC(void)
1159{
1160 int maxlvt;
1161 u32 v;
1162
1163 /* APIC hasn't been mapped yet */
1164 if (!x2apic_mode && !apic_phys)
1165 return;
1166
1167 maxlvt = lapic_get_maxlvt();
1168 /*
1169 * Masking an LVT entry can trigger a local APIC error
1170 * if the vector is zero. Mask LVTERR first to prevent this.
1171 */
1172 if (maxlvt >= 3) {
1173 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
1174 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
1175 }
1176 /*
1177 * Careful: we have to set masks only first to deassert
1178 * any level-triggered sources.
1179 */
1180 v = apic_read(APIC_LVTT);
1181 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
1182 v = apic_read(APIC_LVT0);
1183 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
1184 v = apic_read(APIC_LVT1);
1185 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
1186 if (maxlvt >= 4) {
1187 v = apic_read(APIC_LVTPC);
1188 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
1189 }
1190
1191 /* lets not touch this if we didn't frob it */
1192#ifdef CONFIG_X86_THERMAL_VECTOR
1193 if (maxlvt >= 5) {
1194 v = apic_read(APIC_LVTTHMR);
1195 apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
1196 }
1197#endif
1198#ifdef CONFIG_X86_MCE_INTEL
1199 if (maxlvt >= 6) {
1200 v = apic_read(APIC_LVTCMCI);
1201 if (!(v & APIC_LVT_MASKED))
1202 apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED);
1203 }
1204#endif
1205
1206 /*
1207 * Clean APIC state for other OSs:
1208 */
1209 apic_write(APIC_LVTT, APIC_LVT_MASKED);
1210 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1211 apic_write(APIC_LVT1, APIC_LVT_MASKED);
1212 if (maxlvt >= 3)
1213 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
1214 if (maxlvt >= 4)
1215 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
1216
1217 /* Integrated APIC (!82489DX) ? */
1218 if (lapic_is_integrated()) {
1219 if (maxlvt > 3)
1220 /* Clear ESR due to Pentium errata 3AP and 11AP */
1221 apic_write(APIC_ESR, 0);
1222 apic_read(APIC_ESR);
1223 }
1224}
1225
1226/**
1227 * apic_soft_disable - Clears and software disables the local APIC on hotplug
1228 *
1229 * Contrary to disable_local_APIC() this does not touch the enable bit in
1230 * MSR_IA32_APICBASE. Clearing that bit on systems based on the 3 wire APIC
1231 * bus would require a hardware reset as the APIC would lose track of bus
1232 * arbitration. On systems with FSB delivery APICBASE could be disabled,
1233 * but it has to be guaranteed that no interrupt is sent to the APIC while
1234 * in that state and it's not clear from the SDM whether it still responds
1235 * to INIT/SIPI messages. Stay on the safe side and use software disable.
1236 */
1237void apic_soft_disable(void)
1238{
1239 u32 value;
1240
1241 clear_local_APIC();
1242
1243 /* Soft disable APIC (implies clearing of registers for 82489DX!). */
1244 value = apic_read(APIC_SPIV);
1245 value &= ~APIC_SPIV_APIC_ENABLED;
1246 apic_write(APIC_SPIV, value);
1247}
1248
1249/**
1250 * disable_local_APIC - clear and disable the local APIC
1251 */
1252void disable_local_APIC(void)
1253{
1254 /* APIC hasn't been mapped yet */
1255 if (!x2apic_mode && !apic_phys)
1256 return;
1257
1258 apic_soft_disable();
1259
1260#ifdef CONFIG_X86_32
1261 /*
1262 * When LAPIC was disabled by the BIOS and enabled by the kernel,
1263 * restore the disabled state.
1264 */
1265 if (enabled_via_apicbase) {
1266 unsigned int l, h;
1267
1268 rdmsr(MSR_IA32_APICBASE, l, h);
1269 l &= ~MSR_IA32_APICBASE_ENABLE;
1270 wrmsr(MSR_IA32_APICBASE, l, h);
1271 }
1272#endif
1273}
1274
1275/*
1276 * If Linux enabled the LAPIC against the BIOS default disable it down before
1277 * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
1278 * not power-off. Additionally clear all LVT entries before disable_local_APIC
1279 * for the case where Linux didn't enable the LAPIC.
1280 */
1281void lapic_shutdown(void)
1282{
1283 unsigned long flags;
1284
1285 if (!boot_cpu_has(X86_FEATURE_APIC) && !apic_from_smp_config())
1286 return;
1287
1288 local_irq_save(flags);
1289
1290#ifdef CONFIG_X86_32
1291 if (!enabled_via_apicbase)
1292 clear_local_APIC();
1293 else
1294#endif
1295 disable_local_APIC();
1296
1297
1298 local_irq_restore(flags);
1299}
1300
1301/**
1302 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1303 */
1304void __init sync_Arb_IDs(void)
1305{
1306 /*
1307 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1308 * needed on AMD.
1309 */
1310 if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1311 return;
1312
1313 /*
1314 * Wait for idle.
1315 */
1316 apic_wait_icr_idle();
1317
1318 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1319 apic_write(APIC_ICR, APIC_DEST_ALLINC |
1320 APIC_INT_LEVELTRIG | APIC_DM_INIT);
1321}
1322
1323enum apic_intr_mode_id apic_intr_mode __ro_after_init;
1324
1325static int __init apic_intr_mode_select(void)
1326{
1327 /* Check kernel option */
1328 if (disable_apic) {
1329 pr_info("APIC disabled via kernel command line\n");
1330 return APIC_PIC;
1331 }
1332
1333 /* Check BIOS */
1334#ifdef CONFIG_X86_64
1335 /* On 64-bit, the APIC must be integrated, Check local APIC only */
1336 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1337 disable_apic = 1;
1338 pr_info("APIC disabled by BIOS\n");
1339 return APIC_PIC;
1340 }
1341#else
1342 /* On 32-bit, the APIC may be integrated APIC or 82489DX */
1343
1344 /* Neither 82489DX nor integrated APIC ? */
1345 if (!boot_cpu_has(X86_FEATURE_APIC) && !smp_found_config) {
1346 disable_apic = 1;
1347 return APIC_PIC;
1348 }
1349
1350 /* If the BIOS pretends there is an integrated APIC ? */
1351 if (!boot_cpu_has(X86_FEATURE_APIC) &&
1352 APIC_INTEGRATED(boot_cpu_apic_version)) {
1353 disable_apic = 1;
1354 pr_err(FW_BUG "Local APIC %d not detected, force emulation\n",
1355 boot_cpu_physical_apicid);
1356 return APIC_PIC;
1357 }
1358#endif
1359
1360 /* Check MP table or ACPI MADT configuration */
1361 if (!smp_found_config) {
1362 disable_ioapic_support();
1363 if (!acpi_lapic) {
1364 pr_info("APIC: ACPI MADT or MP tables are not detected\n");
1365 return APIC_VIRTUAL_WIRE_NO_CONFIG;
1366 }
1367 return APIC_VIRTUAL_WIRE;
1368 }
1369
1370#ifdef CONFIG_SMP
1371 /* If SMP should be disabled, then really disable it! */
1372 if (!setup_max_cpus) {
1373 pr_info("APIC: SMP mode deactivated\n");
1374 return APIC_SYMMETRIC_IO_NO_ROUTING;
1375 }
1376
1377 if (read_apic_id() != boot_cpu_physical_apicid) {
1378 panic("Boot APIC ID in local APIC unexpected (%d vs %d)",
1379 read_apic_id(), boot_cpu_physical_apicid);
1380 /* Or can we switch back to PIC here? */
1381 }
1382#endif
1383
1384 return APIC_SYMMETRIC_IO;
1385}
1386
1387/*
1388 * An initial setup of the virtual wire mode.
1389 */
1390void __init init_bsp_APIC(void)
1391{
1392 unsigned int value;
1393
1394 /*
1395 * Don't do the setup now if we have a SMP BIOS as the
1396 * through-I/O-APIC virtual wire mode might be active.
1397 */
1398 if (smp_found_config || !boot_cpu_has(X86_FEATURE_APIC))
1399 return;
1400
1401 /*
1402 * Do not trust the local APIC being empty at bootup.
1403 */
1404 clear_local_APIC();
1405
1406 /*
1407 * Enable APIC.
1408 */
1409 value = apic_read(APIC_SPIV);
1410 value &= ~APIC_VECTOR_MASK;
1411 value |= APIC_SPIV_APIC_ENABLED;
1412
1413#ifdef CONFIG_X86_32
1414 /* This bit is reserved on P4/Xeon and should be cleared */
1415 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1416 (boot_cpu_data.x86 == 15))
1417 value &= ~APIC_SPIV_FOCUS_DISABLED;
1418 else
1419#endif
1420 value |= APIC_SPIV_FOCUS_DISABLED;
1421 value |= SPURIOUS_APIC_VECTOR;
1422 apic_write(APIC_SPIV, value);
1423
1424 /*
1425 * Set up the virtual wire mode.
1426 */
1427 apic_write(APIC_LVT0, APIC_DM_EXTINT);
1428 value = APIC_DM_NMI;
1429 if (!lapic_is_integrated()) /* 82489DX */
1430 value |= APIC_LVT_LEVEL_TRIGGER;
1431 if (apic_extnmi == APIC_EXTNMI_NONE)
1432 value |= APIC_LVT_MASKED;
1433 apic_write(APIC_LVT1, value);
1434}
1435
1436static void __init apic_bsp_setup(bool upmode);
1437
1438/* Init the interrupt delivery mode for the BSP */
1439void __init apic_intr_mode_init(void)
1440{
1441 bool upmode = IS_ENABLED(CONFIG_UP_LATE_INIT);
1442
1443 apic_intr_mode = apic_intr_mode_select();
1444
1445 switch (apic_intr_mode) {
1446 case APIC_PIC:
1447 pr_info("APIC: Keep in PIC mode(8259)\n");
1448 return;
1449 case APIC_VIRTUAL_WIRE:
1450 pr_info("APIC: Switch to virtual wire mode setup\n");
1451 default_setup_apic_routing();
1452 break;
1453 case APIC_VIRTUAL_WIRE_NO_CONFIG:
1454 pr_info("APIC: Switch to virtual wire mode setup with no configuration\n");
1455 upmode = true;
1456 default_setup_apic_routing();
1457 break;
1458 case APIC_SYMMETRIC_IO:
1459 pr_info("APIC: Switch to symmetric I/O mode setup\n");
1460 default_setup_apic_routing();
1461 break;
1462 case APIC_SYMMETRIC_IO_NO_ROUTING:
1463 pr_info("APIC: Switch to symmetric I/O mode setup in no SMP routine\n");
1464 break;
1465 }
1466
1467 apic_bsp_setup(upmode);
1468}
1469
1470static void lapic_setup_esr(void)
1471{
1472 unsigned int oldvalue, value, maxlvt;
1473
1474 if (!lapic_is_integrated()) {
1475 pr_info("No ESR for 82489DX.\n");
1476 return;
1477 }
1478
1479 if (apic->disable_esr) {
1480 /*
1481 * Something untraceable is creating bad interrupts on
1482 * secondary quads ... for the moment, just leave the
1483 * ESR disabled - we can't do anything useful with the
1484 * errors anyway - mbligh
1485 */
1486 pr_info("Leaving ESR disabled.\n");
1487 return;
1488 }
1489
1490 maxlvt = lapic_get_maxlvt();
1491 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
1492 apic_write(APIC_ESR, 0);
1493 oldvalue = apic_read(APIC_ESR);
1494
1495 /* enables sending errors */
1496 value = ERROR_APIC_VECTOR;
1497 apic_write(APIC_LVTERR, value);
1498
1499 /*
1500 * spec says clear errors after enabling vector.
1501 */
1502 if (maxlvt > 3)
1503 apic_write(APIC_ESR, 0);
1504 value = apic_read(APIC_ESR);
1505 if (value != oldvalue)
1506 apic_printk(APIC_VERBOSE, "ESR value before enabling "
1507 "vector: 0x%08x after: 0x%08x\n",
1508 oldvalue, value);
1509}
1510
1511#define APIC_IR_REGS APIC_ISR_NR
1512#define APIC_IR_BITS (APIC_IR_REGS * 32)
1513#define APIC_IR_MAPSIZE (APIC_IR_BITS / BITS_PER_LONG)
1514
1515union apic_ir {
1516 unsigned long map[APIC_IR_MAPSIZE];
1517 u32 regs[APIC_IR_REGS];
1518};
1519
1520static bool apic_check_and_ack(union apic_ir *irr, union apic_ir *isr)
1521{
1522 int i, bit;
1523
1524 /* Read the IRRs */
1525 for (i = 0; i < APIC_IR_REGS; i++)
1526 irr->regs[i] = apic_read(APIC_IRR + i * 0x10);
1527
1528 /* Read the ISRs */
1529 for (i = 0; i < APIC_IR_REGS; i++)
1530 isr->regs[i] = apic_read(APIC_ISR + i * 0x10);
1531
1532 /*
1533 * If the ISR map is not empty. ACK the APIC and run another round
1534 * to verify whether a pending IRR has been unblocked and turned
1535 * into a ISR.
1536 */
1537 if (!bitmap_empty(isr->map, APIC_IR_BITS)) {
1538 /*
1539 * There can be multiple ISR bits set when a high priority
1540 * interrupt preempted a lower priority one. Issue an ACK
1541 * per set bit.
1542 */
1543 for_each_set_bit(bit, isr->map, APIC_IR_BITS)
1544 ack_APIC_irq();
1545 return true;
1546 }
1547
1548 return !bitmap_empty(irr->map, APIC_IR_BITS);
1549}
1550
1551/*
1552 * After a crash, we no longer service the interrupts and a pending
1553 * interrupt from previous kernel might still have ISR bit set.
1554 *
1555 * Most probably by now the CPU has serviced that pending interrupt and it
1556 * might not have done the ack_APIC_irq() because it thought, interrupt
1557 * came from i8259 as ExtInt. LAPIC did not get EOI so it does not clear
1558 * the ISR bit and cpu thinks it has already serivced the interrupt. Hence
1559 * a vector might get locked. It was noticed for timer irq (vector
1560 * 0x31). Issue an extra EOI to clear ISR.
1561 *
1562 * If there are pending IRR bits they turn into ISR bits after a higher
1563 * priority ISR bit has been acked.
1564 */
1565static void apic_pending_intr_clear(void)
1566{
1567 union apic_ir irr, isr;
1568 unsigned int i;
1569
1570 /* 512 loops are way oversized and give the APIC a chance to obey. */
1571 for (i = 0; i < 512; i++) {
1572 if (!apic_check_and_ack(&irr, &isr))
1573 return;
1574 }
1575 /* Dump the IRR/ISR content if that failed */
1576 pr_warn("APIC: Stale IRR: %256pb ISR: %256pb\n", irr.map, isr.map);
1577}
1578
1579/**
1580 * setup_local_APIC - setup the local APIC
1581 *
1582 * Used to setup local APIC while initializing BSP or bringing up APs.
1583 * Always called with preemption disabled.
1584 */
1585static void setup_local_APIC(void)
1586{
1587 int cpu = smp_processor_id();
1588 unsigned int value;
1589
1590 if (disable_apic) {
1591 disable_ioapic_support();
1592 return;
1593 }
1594
1595 /*
1596 * If this comes from kexec/kcrash the APIC might be enabled in
1597 * SPIV. Soft disable it before doing further initialization.
1598 */
1599 value = apic_read(APIC_SPIV);
1600 value &= ~APIC_SPIV_APIC_ENABLED;
1601 apic_write(APIC_SPIV, value);
1602
1603#ifdef CONFIG_X86_32
1604 /* Pound the ESR really hard over the head with a big hammer - mbligh */
1605 if (lapic_is_integrated() && apic->disable_esr) {
1606 apic_write(APIC_ESR, 0);
1607 apic_write(APIC_ESR, 0);
1608 apic_write(APIC_ESR, 0);
1609 apic_write(APIC_ESR, 0);
1610 }
1611#endif
1612 /*
1613 * Double-check whether this APIC is really registered.
1614 * This is meaningless in clustered apic mode, so we skip it.
1615 */
1616 BUG_ON(!apic->apic_id_registered());
1617
1618 /*
1619 * Intel recommends to set DFR, LDR and TPR before enabling
1620 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
1621 * document number 292116). So here it goes...
1622 */
1623 apic->init_apic_ldr();
1624
1625#ifdef CONFIG_X86_32
1626 if (apic->dest_logical) {
1627 int logical_apicid, ldr_apicid;
1628
1629 /*
1630 * APIC LDR is initialized. If logical_apicid mapping was
1631 * initialized during get_smp_config(), make sure it matches
1632 * the actual value.
1633 */
1634 logical_apicid = early_per_cpu(x86_cpu_to_logical_apicid, cpu);
1635 ldr_apicid = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR));
1636 if (logical_apicid != BAD_APICID)
1637 WARN_ON(logical_apicid != ldr_apicid);
1638 /* Always use the value from LDR. */
1639 early_per_cpu(x86_cpu_to_logical_apicid, cpu) = ldr_apicid;
1640 }
1641#endif
1642
1643 /*
1644 * Set Task Priority to 'accept all except vectors 0-31'. An APIC
1645 * vector in the 16-31 range could be delivered if TPR == 0, but we
1646 * would think it's an exception and terrible things will happen. We
1647 * never change this later on.
1648 */
1649 value = apic_read(APIC_TASKPRI);
1650 value &= ~APIC_TPRI_MASK;
1651 value |= 0x10;
1652 apic_write(APIC_TASKPRI, value);
1653
1654 /* Clear eventually stale ISR/IRR bits */
1655 apic_pending_intr_clear();
1656
1657 /*
1658 * Now that we are all set up, enable the APIC
1659 */
1660 value = apic_read(APIC_SPIV);
1661 value &= ~APIC_VECTOR_MASK;
1662 /*
1663 * Enable APIC
1664 */
1665 value |= APIC_SPIV_APIC_ENABLED;
1666
1667#ifdef CONFIG_X86_32
1668 /*
1669 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1670 * certain networking cards. If high frequency interrupts are
1671 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1672 * entry is masked/unmasked at a high rate as well then sooner or
1673 * later IOAPIC line gets 'stuck', no more interrupts are received
1674 * from the device. If focus CPU is disabled then the hang goes
1675 * away, oh well :-(
1676 *
1677 * [ This bug can be reproduced easily with a level-triggered
1678 * PCI Ne2000 networking cards and PII/PIII processors, dual
1679 * BX chipset. ]
1680 */
1681 /*
1682 * Actually disabling the focus CPU check just makes the hang less
1683 * frequent as it makes the interrupt distributon model be more
1684 * like LRU than MRU (the short-term load is more even across CPUs).
1685 */
1686
1687 /*
1688 * - enable focus processor (bit==0)
1689 * - 64bit mode always use processor focus
1690 * so no need to set it
1691 */
1692 value &= ~APIC_SPIV_FOCUS_DISABLED;
1693#endif
1694
1695 /*
1696 * Set spurious IRQ vector
1697 */
1698 value |= SPURIOUS_APIC_VECTOR;
1699 apic_write(APIC_SPIV, value);
1700
1701 perf_events_lapic_init();
1702
1703 /*
1704 * Set up LVT0, LVT1:
1705 *
1706 * set up through-local-APIC on the boot CPU's LINT0. This is not
1707 * strictly necessary in pure symmetric-IO mode, but sometimes
1708 * we delegate interrupts to the 8259A.
1709 */
1710 /*
1711 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1712 */
1713 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1714 if (!cpu && (pic_mode || !value || skip_ioapic_setup)) {
1715 value = APIC_DM_EXTINT;
1716 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n", cpu);
1717 } else {
1718 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1719 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n", cpu);
1720 }
1721 apic_write(APIC_LVT0, value);
1722
1723 /*
1724 * Only the BSP sees the LINT1 NMI signal by default. This can be
1725 * modified by apic_extnmi= boot option.
1726 */
1727 if ((!cpu && apic_extnmi != APIC_EXTNMI_NONE) ||
1728 apic_extnmi == APIC_EXTNMI_ALL)
1729 value = APIC_DM_NMI;
1730 else
1731 value = APIC_DM_NMI | APIC_LVT_MASKED;
1732
1733 /* Is 82489DX ? */
1734 if (!lapic_is_integrated())
1735 value |= APIC_LVT_LEVEL_TRIGGER;
1736 apic_write(APIC_LVT1, value);
1737
1738#ifdef CONFIG_X86_MCE_INTEL
1739 /* Recheck CMCI information after local APIC is up on CPU #0 */
1740 if (!cpu)
1741 cmci_recheck();
1742#endif
1743}
1744
1745static void end_local_APIC_setup(void)
1746{
1747 lapic_setup_esr();
1748
1749#ifdef CONFIG_X86_32
1750 {
1751 unsigned int value;
1752 /* Disable the local apic timer */
1753 value = apic_read(APIC_LVTT);
1754 value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1755 apic_write(APIC_LVTT, value);
1756 }
1757#endif
1758
1759 apic_pm_activate();
1760}
1761
1762/*
1763 * APIC setup function for application processors. Called from smpboot.c
1764 */
1765void apic_ap_setup(void)
1766{
1767 setup_local_APIC();
1768 end_local_APIC_setup();
1769}
1770
1771#ifdef CONFIG_X86_X2APIC
1772int x2apic_mode;
1773
1774enum {
1775 X2APIC_OFF,
1776 X2APIC_ON,
1777 X2APIC_DISABLED,
1778};
1779static int x2apic_state;
1780
1781static void __x2apic_disable(void)
1782{
1783 u64 msr;
1784
1785 if (!boot_cpu_has(X86_FEATURE_APIC))
1786 return;
1787
1788 rdmsrl(MSR_IA32_APICBASE, msr);
1789 if (!(msr & X2APIC_ENABLE))
1790 return;
1791 /* Disable xapic and x2apic first and then reenable xapic mode */
1792 wrmsrl(MSR_IA32_APICBASE, msr & ~(X2APIC_ENABLE | XAPIC_ENABLE));
1793 wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE);
1794 printk_once(KERN_INFO "x2apic disabled\n");
1795}
1796
1797static void __x2apic_enable(void)
1798{
1799 u64 msr;
1800
1801 rdmsrl(MSR_IA32_APICBASE, msr);
1802 if (msr & X2APIC_ENABLE)
1803 return;
1804 wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE);
1805 printk_once(KERN_INFO "x2apic enabled\n");
1806}
1807
1808static int __init setup_nox2apic(char *str)
1809{
1810 if (x2apic_enabled()) {
1811 int apicid = native_apic_msr_read(APIC_ID);
1812
1813 if (apicid >= 255) {
1814 pr_warning("Apicid: %08x, cannot enforce nox2apic\n",
1815 apicid);
1816 return 0;
1817 }
1818 pr_warning("x2apic already enabled.\n");
1819 __x2apic_disable();
1820 }
1821 setup_clear_cpu_cap(X86_FEATURE_X2APIC);
1822 x2apic_state = X2APIC_DISABLED;
1823 x2apic_mode = 0;
1824 return 0;
1825}
1826early_param("nox2apic", setup_nox2apic);
1827
1828/* Called from cpu_init() to enable x2apic on (secondary) cpus */
1829void x2apic_setup(void)
1830{
1831 /*
1832 * If x2apic is not in ON state, disable it if already enabled
1833 * from BIOS.
1834 */
1835 if (x2apic_state != X2APIC_ON) {
1836 __x2apic_disable();
1837 return;
1838 }
1839 __x2apic_enable();
1840}
1841
1842static __init void x2apic_disable(void)
1843{
1844 u32 x2apic_id, state = x2apic_state;
1845
1846 x2apic_mode = 0;
1847 x2apic_state = X2APIC_DISABLED;
1848
1849 if (state != X2APIC_ON)
1850 return;
1851
1852 x2apic_id = read_apic_id();
1853 if (x2apic_id >= 255)
1854 panic("Cannot disable x2apic, id: %08x\n", x2apic_id);
1855
1856 __x2apic_disable();
1857 register_lapic_address(mp_lapic_addr);
1858}
1859
1860static __init void x2apic_enable(void)
1861{
1862 if (x2apic_state != X2APIC_OFF)
1863 return;
1864
1865 x2apic_mode = 1;
1866 x2apic_state = X2APIC_ON;
1867 __x2apic_enable();
1868}
1869
1870static __init void try_to_enable_x2apic(int remap_mode)
1871{
1872 if (x2apic_state == X2APIC_DISABLED)
1873 return;
1874
1875 if (remap_mode != IRQ_REMAP_X2APIC_MODE) {
1876 /* IR is required if there is APIC ID > 255 even when running
1877 * under KVM
1878 */
1879 if (max_physical_apicid > 255 ||
1880 !x86_init.hyper.x2apic_available()) {
1881 pr_info("x2apic: IRQ remapping doesn't support X2APIC mode\n");
1882 x2apic_disable();
1883 return;
1884 }
1885
1886 /*
1887 * without IR all CPUs can be addressed by IOAPIC/MSI
1888 * only in physical mode
1889 */
1890 x2apic_phys = 1;
1891 }
1892 x2apic_enable();
1893}
1894
1895void __init check_x2apic(void)
1896{
1897 if (x2apic_enabled()) {
1898 pr_info("x2apic: enabled by BIOS, switching to x2apic ops\n");
1899 x2apic_mode = 1;
1900 x2apic_state = X2APIC_ON;
1901 } else if (!boot_cpu_has(X86_FEATURE_X2APIC)) {
1902 x2apic_state = X2APIC_DISABLED;
1903 }
1904}
1905#else /* CONFIG_X86_X2APIC */
1906static int __init validate_x2apic(void)
1907{
1908 if (!apic_is_x2apic_enabled())
1909 return 0;
1910 /*
1911 * Checkme: Can we simply turn off x2apic here instead of panic?
1912 */
1913 panic("BIOS has enabled x2apic but kernel doesn't support x2apic, please disable x2apic in BIOS.\n");
1914}
1915early_initcall(validate_x2apic);
1916
1917static inline void try_to_enable_x2apic(int remap_mode) { }
1918static inline void __x2apic_enable(void) { }
1919#endif /* !CONFIG_X86_X2APIC */
1920
1921void __init enable_IR_x2apic(void)
1922{
1923 unsigned long flags;
1924 int ret, ir_stat;
1925
1926 if (skip_ioapic_setup) {
1927 pr_info("Not enabling interrupt remapping due to skipped IO-APIC setup\n");
1928 return;
1929 }
1930
1931 ir_stat = irq_remapping_prepare();
1932 if (ir_stat < 0 && !x2apic_supported())
1933 return;
1934
1935 ret = save_ioapic_entries();
1936 if (ret) {
1937 pr_info("Saving IO-APIC state failed: %d\n", ret);
1938 return;
1939 }
1940
1941 local_irq_save(flags);
1942 legacy_pic->mask_all();
1943 mask_ioapic_entries();
1944
1945 /* If irq_remapping_prepare() succeeded, try to enable it */
1946 if (ir_stat >= 0)
1947 ir_stat = irq_remapping_enable();
1948 /* ir_stat contains the remap mode or an error code */
1949 try_to_enable_x2apic(ir_stat);
1950
1951 if (ir_stat < 0)
1952 restore_ioapic_entries();
1953 legacy_pic->restore_mask();
1954 local_irq_restore(flags);
1955}
1956
1957#ifdef CONFIG_X86_64
1958/*
1959 * Detect and enable local APICs on non-SMP boards.
1960 * Original code written by Keir Fraser.
1961 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1962 * not correctly set up (usually the APIC timer won't work etc.)
1963 */
1964static int __init detect_init_APIC(void)
1965{
1966 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1967 pr_info("No local APIC present\n");
1968 return -1;
1969 }
1970
1971 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1972 return 0;
1973}
1974#else
1975
1976static int __init apic_verify(void)
1977{
1978 u32 features, h, l;
1979
1980 /*
1981 * The APIC feature bit should now be enabled
1982 * in `cpuid'
1983 */
1984 features = cpuid_edx(1);
1985 if (!(features & (1 << X86_FEATURE_APIC))) {
1986 pr_warning("Could not enable APIC!\n");
1987 return -1;
1988 }
1989 set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1990 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1991
1992 /* The BIOS may have set up the APIC at some other address */
1993 if (boot_cpu_data.x86 >= 6) {
1994 rdmsr(MSR_IA32_APICBASE, l, h);
1995 if (l & MSR_IA32_APICBASE_ENABLE)
1996 mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
1997 }
1998
1999 pr_info("Found and enabled local APIC!\n");
2000 return 0;
2001}
2002
2003int __init apic_force_enable(unsigned long addr)
2004{
2005 u32 h, l;
2006
2007 if (disable_apic)
2008 return -1;
2009
2010 /*
2011 * Some BIOSes disable the local APIC in the APIC_BASE
2012 * MSR. This can only be done in software for Intel P6 or later
2013 * and AMD K7 (Model > 1) or later.
2014 */
2015 if (boot_cpu_data.x86 >= 6) {
2016 rdmsr(MSR_IA32_APICBASE, l, h);
2017 if (!(l & MSR_IA32_APICBASE_ENABLE)) {
2018 pr_info("Local APIC disabled by BIOS -- reenabling.\n");
2019 l &= ~MSR_IA32_APICBASE_BASE;
2020 l |= MSR_IA32_APICBASE_ENABLE | addr;
2021 wrmsr(MSR_IA32_APICBASE, l, h);
2022 enabled_via_apicbase = 1;
2023 }
2024 }
2025 return apic_verify();
2026}
2027
2028/*
2029 * Detect and initialize APIC
2030 */
2031static int __init detect_init_APIC(void)
2032{
2033 /* Disabled by kernel option? */
2034 if (disable_apic)
2035 return -1;
2036
2037 switch (boot_cpu_data.x86_vendor) {
2038 case X86_VENDOR_AMD:
2039 if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
2040 (boot_cpu_data.x86 >= 15))
2041 break;
2042 goto no_apic;
2043 case X86_VENDOR_HYGON:
2044 break;
2045 case X86_VENDOR_INTEL:
2046 if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
2047 (boot_cpu_data.x86 == 5 && boot_cpu_has(X86_FEATURE_APIC)))
2048 break;
2049 goto no_apic;
2050 default:
2051 goto no_apic;
2052 }
2053
2054 if (!boot_cpu_has(X86_FEATURE_APIC)) {
2055 /*
2056 * Over-ride BIOS and try to enable the local APIC only if
2057 * "lapic" specified.
2058 */
2059 if (!force_enable_local_apic) {
2060 pr_info("Local APIC disabled by BIOS -- "
2061 "you can enable it with \"lapic\"\n");
2062 return -1;
2063 }
2064 if (apic_force_enable(APIC_DEFAULT_PHYS_BASE))
2065 return -1;
2066 } else {
2067 if (apic_verify())
2068 return -1;
2069 }
2070
2071 apic_pm_activate();
2072
2073 return 0;
2074
2075no_apic:
2076 pr_info("No local APIC present or hardware disabled\n");
2077 return -1;
2078}
2079#endif
2080
2081/**
2082 * init_apic_mappings - initialize APIC mappings
2083 */
2084void __init init_apic_mappings(void)
2085{
2086 unsigned int new_apicid;
2087
2088 apic_check_deadline_errata();
2089
2090 if (x2apic_mode) {
2091 boot_cpu_physical_apicid = read_apic_id();
2092 return;
2093 }
2094
2095 /* If no local APIC can be found return early */
2096 if (!smp_found_config && detect_init_APIC()) {
2097 /* lets NOP'ify apic operations */
2098 pr_info("APIC: disable apic facility\n");
2099 apic_disable();
2100 } else {
2101 apic_phys = mp_lapic_addr;
2102
2103 /*
2104 * If the system has ACPI MADT tables or MP info, the LAPIC
2105 * address is already registered.
2106 */
2107 if (!acpi_lapic && !smp_found_config)
2108 register_lapic_address(apic_phys);
2109 }
2110
2111 /*
2112 * Fetch the APIC ID of the BSP in case we have a
2113 * default configuration (or the MP table is broken).
2114 */
2115 new_apicid = read_apic_id();
2116 if (boot_cpu_physical_apicid != new_apicid) {
2117 boot_cpu_physical_apicid = new_apicid;
2118 /*
2119 * yeah -- we lie about apic_version
2120 * in case if apic was disabled via boot option
2121 * but it's not a problem for SMP compiled kernel
2122 * since apic_intr_mode_select is prepared for such
2123 * a case and disable smp mode
2124 */
2125 boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
2126 }
2127}
2128
2129void __init register_lapic_address(unsigned long address)
2130{
2131 mp_lapic_addr = address;
2132
2133 if (!x2apic_mode) {
2134 set_fixmap_nocache(FIX_APIC_BASE, address);
2135 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
2136 APIC_BASE, address);
2137 }
2138 if (boot_cpu_physical_apicid == -1U) {
2139 boot_cpu_physical_apicid = read_apic_id();
2140 boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
2141 }
2142}
2143
2144/*
2145 * Local APIC interrupts
2146 */
2147
2148/*
2149 * This interrupt should _never_ happen with our APIC/SMP architecture
2150 */
2151__visible void __irq_entry smp_spurious_interrupt(struct pt_regs *regs)
2152{
2153 u8 vector = ~regs->orig_ax;
2154 u32 v;
2155
2156 entering_irq();
2157 trace_spurious_apic_entry(vector);
2158
2159 inc_irq_stat(irq_spurious_count);
2160
2161 /*
2162 * If this is a spurious interrupt then do not acknowledge
2163 */
2164 if (vector == SPURIOUS_APIC_VECTOR) {
2165 /* See SDM vol 3 */
2166 pr_info("Spurious APIC interrupt (vector 0xFF) on CPU#%d, should never happen.\n",
2167 smp_processor_id());
2168 goto out;
2169 }
2170
2171 /*
2172 * If it is a vectored one, verify it's set in the ISR. If set,
2173 * acknowledge it.
2174 */
2175 v = apic_read(APIC_ISR + ((vector & ~0x1f) >> 1));
2176 if (v & (1 << (vector & 0x1f))) {
2177 pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Acked\n",
2178 vector, smp_processor_id());
2179 ack_APIC_irq();
2180 } else {
2181 pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Not pending!\n",
2182 vector, smp_processor_id());
2183 }
2184out:
2185 trace_spurious_apic_exit(vector);
2186 exiting_irq();
2187}
2188
2189/*
2190 * This interrupt should never happen with our APIC/SMP architecture
2191 */
2192__visible void __irq_entry smp_error_interrupt(struct pt_regs *regs)
2193{
2194 static const char * const error_interrupt_reason[] = {
2195 "Send CS error", /* APIC Error Bit 0 */
2196 "Receive CS error", /* APIC Error Bit 1 */
2197 "Send accept error", /* APIC Error Bit 2 */
2198 "Receive accept error", /* APIC Error Bit 3 */
2199 "Redirectable IPI", /* APIC Error Bit 4 */
2200 "Send illegal vector", /* APIC Error Bit 5 */
2201 "Received illegal vector", /* APIC Error Bit 6 */
2202 "Illegal register address", /* APIC Error Bit 7 */
2203 };
2204 u32 v, i = 0;
2205
2206 entering_irq();
2207 trace_error_apic_entry(ERROR_APIC_VECTOR);
2208
2209 /* First tickle the hardware, only then report what went on. -- REW */
2210 if (lapic_get_maxlvt() > 3) /* Due to the Pentium erratum 3AP. */
2211 apic_write(APIC_ESR, 0);
2212 v = apic_read(APIC_ESR);
2213 ack_APIC_irq();
2214 atomic_inc(&irq_err_count);
2215
2216 apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x",
2217 smp_processor_id(), v);
2218
2219 v &= 0xff;
2220 while (v) {
2221 if (v & 0x1)
2222 apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]);
2223 i++;
2224 v >>= 1;
2225 }
2226
2227 apic_printk(APIC_DEBUG, KERN_CONT "\n");
2228
2229 trace_error_apic_exit(ERROR_APIC_VECTOR);
2230 exiting_irq();
2231}
2232
2233/**
2234 * connect_bsp_APIC - attach the APIC to the interrupt system
2235 */
2236static void __init connect_bsp_APIC(void)
2237{
2238#ifdef CONFIG_X86_32
2239 if (pic_mode) {
2240 /*
2241 * Do not trust the local APIC being empty at bootup.
2242 */
2243 clear_local_APIC();
2244 /*
2245 * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
2246 * local APIC to INT and NMI lines.
2247 */
2248 apic_printk(APIC_VERBOSE, "leaving PIC mode, "
2249 "enabling APIC mode.\n");
2250 imcr_pic_to_apic();
2251 }
2252#endif
2253}
2254
2255/**
2256 * disconnect_bsp_APIC - detach the APIC from the interrupt system
2257 * @virt_wire_setup: indicates, whether virtual wire mode is selected
2258 *
2259 * Virtual wire mode is necessary to deliver legacy interrupts even when the
2260 * APIC is disabled.
2261 */
2262void disconnect_bsp_APIC(int virt_wire_setup)
2263{
2264 unsigned int value;
2265
2266#ifdef CONFIG_X86_32
2267 if (pic_mode) {
2268 /*
2269 * Put the board back into PIC mode (has an effect only on
2270 * certain older boards). Note that APIC interrupts, including
2271 * IPIs, won't work beyond this point! The only exception are
2272 * INIT IPIs.
2273 */
2274 apic_printk(APIC_VERBOSE, "disabling APIC mode, "
2275 "entering PIC mode.\n");
2276 imcr_apic_to_pic();
2277 return;
2278 }
2279#endif
2280
2281 /* Go back to Virtual Wire compatibility mode */
2282
2283 /* For the spurious interrupt use vector F, and enable it */
2284 value = apic_read(APIC_SPIV);
2285 value &= ~APIC_VECTOR_MASK;
2286 value |= APIC_SPIV_APIC_ENABLED;
2287 value |= 0xf;
2288 apic_write(APIC_SPIV, value);
2289
2290 if (!virt_wire_setup) {
2291 /*
2292 * For LVT0 make it edge triggered, active high,
2293 * external and enabled
2294 */
2295 value = apic_read(APIC_LVT0);
2296 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2297 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2298 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2299 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2300 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
2301 apic_write(APIC_LVT0, value);
2302 } else {
2303 /* Disable LVT0 */
2304 apic_write(APIC_LVT0, APIC_LVT_MASKED);
2305 }
2306
2307 /*
2308 * For LVT1 make it edge triggered, active high,
2309 * nmi and enabled
2310 */
2311 value = apic_read(APIC_LVT1);
2312 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2313 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2314 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2315 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2316 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
2317 apic_write(APIC_LVT1, value);
2318}
2319
2320/*
2321 * The number of allocated logical CPU IDs. Since logical CPU IDs are allocated
2322 * contiguously, it equals to current allocated max logical CPU ID plus 1.
2323 * All allocated CPU IDs should be in the [0, nr_logical_cpuids) range,
2324 * so the maximum of nr_logical_cpuids is nr_cpu_ids.
2325 *
2326 * NOTE: Reserve 0 for BSP.
2327 */
2328static int nr_logical_cpuids = 1;
2329
2330/*
2331 * Used to store mapping between logical CPU IDs and APIC IDs.
2332 */
2333static int cpuid_to_apicid[] = {
2334 [0 ... NR_CPUS - 1] = -1,
2335};
2336
2337#ifdef CONFIG_SMP
2338/**
2339 * apic_id_is_primary_thread - Check whether APIC ID belongs to a primary thread
2340 * @id: APIC ID to check
2341 */
2342bool apic_id_is_primary_thread(unsigned int apicid)
2343{
2344 u32 mask;
2345
2346 if (smp_num_siblings == 1)
2347 return true;
2348 /* Isolate the SMT bit(s) in the APICID and check for 0 */
2349 mask = (1U << (fls(smp_num_siblings) - 1)) - 1;
2350 return !(apicid & mask);
2351}
2352#endif
2353
2354/*
2355 * Should use this API to allocate logical CPU IDs to keep nr_logical_cpuids
2356 * and cpuid_to_apicid[] synchronized.
2357 */
2358static int allocate_logical_cpuid(int apicid)
2359{
2360 int i;
2361
2362 /*
2363 * cpuid <-> apicid mapping is persistent, so when a cpu is up,
2364 * check if the kernel has allocated a cpuid for it.
2365 */
2366 for (i = 0; i < nr_logical_cpuids; i++) {
2367 if (cpuid_to_apicid[i] == apicid)
2368 return i;
2369 }
2370
2371 /* Allocate a new cpuid. */
2372 if (nr_logical_cpuids >= nr_cpu_ids) {
2373 WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %u reached. "
2374 "Processor %d/0x%x and the rest are ignored.\n",
2375 nr_cpu_ids, nr_logical_cpuids, apicid);
2376 return -EINVAL;
2377 }
2378
2379 cpuid_to_apicid[nr_logical_cpuids] = apicid;
2380 return nr_logical_cpuids++;
2381}
2382
2383int generic_processor_info(int apicid, int version)
2384{
2385 int cpu, max = nr_cpu_ids;
2386 bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid,
2387 phys_cpu_present_map);
2388
2389 /*
2390 * boot_cpu_physical_apicid is designed to have the apicid
2391 * returned by read_apic_id(), i.e, the apicid of the
2392 * currently booting-up processor. However, on some platforms,
2393 * it is temporarily modified by the apicid reported as BSP
2394 * through MP table. Concretely:
2395 *
2396 * - arch/x86/kernel/mpparse.c: MP_processor_info()
2397 * - arch/x86/mm/amdtopology.c: amd_numa_init()
2398 *
2399 * This function is executed with the modified
2400 * boot_cpu_physical_apicid. So, disabled_cpu_apicid kernel
2401 * parameter doesn't work to disable APs on kdump 2nd kernel.
2402 *
2403 * Since fixing handling of boot_cpu_physical_apicid requires
2404 * another discussion and tests on each platform, we leave it
2405 * for now and here we use read_apic_id() directly in this
2406 * function, generic_processor_info().
2407 */
2408 if (disabled_cpu_apicid != BAD_APICID &&
2409 disabled_cpu_apicid != read_apic_id() &&
2410 disabled_cpu_apicid == apicid) {
2411 int thiscpu = num_processors + disabled_cpus;
2412
2413 pr_warning("APIC: Disabling requested cpu."
2414 " Processor %d/0x%x ignored.\n",
2415 thiscpu, apicid);
2416
2417 disabled_cpus++;
2418 return -ENODEV;
2419 }
2420
2421 /*
2422 * If boot cpu has not been detected yet, then only allow upto
2423 * nr_cpu_ids - 1 processors and keep one slot free for boot cpu
2424 */
2425 if (!boot_cpu_detected && num_processors >= nr_cpu_ids - 1 &&
2426 apicid != boot_cpu_physical_apicid) {
2427 int thiscpu = max + disabled_cpus - 1;
2428
2429 pr_warning(
2430 "APIC: NR_CPUS/possible_cpus limit of %i almost"
2431 " reached. Keeping one slot for boot cpu."
2432 " Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
2433
2434 disabled_cpus++;
2435 return -ENODEV;
2436 }
2437
2438 if (num_processors >= nr_cpu_ids) {
2439 int thiscpu = max + disabled_cpus;
2440
2441 pr_warning("APIC: NR_CPUS/possible_cpus limit of %i "
2442 "reached. Processor %d/0x%x ignored.\n",
2443 max, thiscpu, apicid);
2444
2445 disabled_cpus++;
2446 return -EINVAL;
2447 }
2448
2449 if (apicid == boot_cpu_physical_apicid) {
2450 /*
2451 * x86_bios_cpu_apicid is required to have processors listed
2452 * in same order as logical cpu numbers. Hence the first
2453 * entry is BSP, and so on.
2454 * boot_cpu_init() already hold bit 0 in cpu_present_mask
2455 * for BSP.
2456 */
2457 cpu = 0;
2458
2459 /* Logical cpuid 0 is reserved for BSP. */
2460 cpuid_to_apicid[0] = apicid;
2461 } else {
2462 cpu = allocate_logical_cpuid(apicid);
2463 if (cpu < 0) {
2464 disabled_cpus++;
2465 return -EINVAL;
2466 }
2467 }
2468
2469 /*
2470 * Validate version
2471 */
2472 if (version == 0x0) {
2473 pr_warning("BIOS bug: APIC version is 0 for CPU %d/0x%x, fixing up to 0x10\n",
2474 cpu, apicid);
2475 version = 0x10;
2476 }
2477
2478 if (version != boot_cpu_apic_version) {
2479 pr_warning("BIOS bug: APIC version mismatch, boot CPU: %x, CPU %d: version %x\n",
2480 boot_cpu_apic_version, cpu, version);
2481 }
2482
2483 if (apicid > max_physical_apicid)
2484 max_physical_apicid = apicid;
2485
2486#if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
2487 early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
2488 early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
2489#endif
2490#ifdef CONFIG_X86_32
2491 early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
2492 apic->x86_32_early_logical_apicid(cpu);
2493#endif
2494 set_cpu_possible(cpu, true);
2495 physid_set(apicid, phys_cpu_present_map);
2496 set_cpu_present(cpu, true);
2497 num_processors++;
2498
2499 return cpu;
2500}
2501
2502int hard_smp_processor_id(void)
2503{
2504 return read_apic_id();
2505}
2506
2507/*
2508 * Override the generic EOI implementation with an optimized version.
2509 * Only called during early boot when only one CPU is active and with
2510 * interrupts disabled, so we know this does not race with actual APIC driver
2511 * use.
2512 */
2513void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v))
2514{
2515 struct apic **drv;
2516
2517 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
2518 /* Should happen once for each apic */
2519 WARN_ON((*drv)->eoi_write == eoi_write);
2520 (*drv)->native_eoi_write = (*drv)->eoi_write;
2521 (*drv)->eoi_write = eoi_write;
2522 }
2523}
2524
2525static void __init apic_bsp_up_setup(void)
2526{
2527#ifdef CONFIG_X86_64
2528 apic_write(APIC_ID, apic->set_apic_id(boot_cpu_physical_apicid));
2529#else
2530 /*
2531 * Hack: In case of kdump, after a crash, kernel might be booting
2532 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
2533 * might be zero if read from MP tables. Get it from LAPIC.
2534 */
2535# ifdef CONFIG_CRASH_DUMP
2536 boot_cpu_physical_apicid = read_apic_id();
2537# endif
2538#endif
2539 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
2540}
2541
2542/**
2543 * apic_bsp_setup - Setup function for local apic and io-apic
2544 * @upmode: Force UP mode (for APIC_init_uniprocessor)
2545 */
2546static void __init apic_bsp_setup(bool upmode)
2547{
2548 connect_bsp_APIC();
2549 if (upmode)
2550 apic_bsp_up_setup();
2551 setup_local_APIC();
2552
2553 enable_IO_APIC();
2554 end_local_APIC_setup();
2555 irq_remap_enable_fault_handling();
2556 setup_IO_APIC();
2557}
2558
2559#ifdef CONFIG_UP_LATE_INIT
2560void __init up_late_init(void)
2561{
2562 if (apic_intr_mode == APIC_PIC)
2563 return;
2564
2565 /* Setup local timer */
2566 x86_init.timers.setup_percpu_clockev();
2567}
2568#endif
2569
2570/*
2571 * Power management
2572 */
2573#ifdef CONFIG_PM
2574
2575static struct {
2576 /*
2577 * 'active' is true if the local APIC was enabled by us and
2578 * not the BIOS; this signifies that we are also responsible
2579 * for disabling it before entering apm/acpi suspend
2580 */
2581 int active;
2582 /* r/w apic fields */
2583 unsigned int apic_id;
2584 unsigned int apic_taskpri;
2585 unsigned int apic_ldr;
2586 unsigned int apic_dfr;
2587 unsigned int apic_spiv;
2588 unsigned int apic_lvtt;
2589 unsigned int apic_lvtpc;
2590 unsigned int apic_lvt0;
2591 unsigned int apic_lvt1;
2592 unsigned int apic_lvterr;
2593 unsigned int apic_tmict;
2594 unsigned int apic_tdcr;
2595 unsigned int apic_thmr;
2596 unsigned int apic_cmci;
2597} apic_pm_state;
2598
2599static int lapic_suspend(void)
2600{
2601 unsigned long flags;
2602 int maxlvt;
2603
2604 if (!apic_pm_state.active)
2605 return 0;
2606
2607 maxlvt = lapic_get_maxlvt();
2608
2609 apic_pm_state.apic_id = apic_read(APIC_ID);
2610 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
2611 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
2612 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
2613 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
2614 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
2615 if (maxlvt >= 4)
2616 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
2617 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
2618 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
2619 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
2620 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
2621 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
2622#ifdef CONFIG_X86_THERMAL_VECTOR
2623 if (maxlvt >= 5)
2624 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
2625#endif
2626#ifdef CONFIG_X86_MCE_INTEL
2627 if (maxlvt >= 6)
2628 apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
2629#endif
2630
2631 local_irq_save(flags);
2632 disable_local_APIC();
2633
2634 irq_remapping_disable();
2635
2636 local_irq_restore(flags);
2637 return 0;
2638}
2639
2640static void lapic_resume(void)
2641{
2642 unsigned int l, h;
2643 unsigned long flags;
2644 int maxlvt;
2645
2646 if (!apic_pm_state.active)
2647 return;
2648
2649 local_irq_save(flags);
2650
2651 /*
2652 * IO-APIC and PIC have their own resume routines.
2653 * We just mask them here to make sure the interrupt
2654 * subsystem is completely quiet while we enable x2apic
2655 * and interrupt-remapping.
2656 */
2657 mask_ioapic_entries();
2658 legacy_pic->mask_all();
2659
2660 if (x2apic_mode) {
2661 __x2apic_enable();
2662 } else {
2663 /*
2664 * Make sure the APICBASE points to the right address
2665 *
2666 * FIXME! This will be wrong if we ever support suspend on
2667 * SMP! We'll need to do this as part of the CPU restore!
2668 */
2669 if (boot_cpu_data.x86 >= 6) {
2670 rdmsr(MSR_IA32_APICBASE, l, h);
2671 l &= ~MSR_IA32_APICBASE_BASE;
2672 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
2673 wrmsr(MSR_IA32_APICBASE, l, h);
2674 }
2675 }
2676
2677 maxlvt = lapic_get_maxlvt();
2678 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
2679 apic_write(APIC_ID, apic_pm_state.apic_id);
2680 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2681 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2682 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2683 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2684 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2685 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2686#ifdef CONFIG_X86_THERMAL_VECTOR
2687 if (maxlvt >= 5)
2688 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2689#endif
2690#ifdef CONFIG_X86_MCE_INTEL
2691 if (maxlvt >= 6)
2692 apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
2693#endif
2694 if (maxlvt >= 4)
2695 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2696 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2697 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2698 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2699 apic_write(APIC_ESR, 0);
2700 apic_read(APIC_ESR);
2701 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2702 apic_write(APIC_ESR, 0);
2703 apic_read(APIC_ESR);
2704
2705 irq_remapping_reenable(x2apic_mode);
2706
2707 local_irq_restore(flags);
2708}
2709
2710/*
2711 * This device has no shutdown method - fully functioning local APICs
2712 * are needed on every CPU up until machine_halt/restart/poweroff.
2713 */
2714
2715static struct syscore_ops lapic_syscore_ops = {
2716 .resume = lapic_resume,
2717 .suspend = lapic_suspend,
2718};
2719
2720static void apic_pm_activate(void)
2721{
2722 apic_pm_state.active = 1;
2723}
2724
2725static int __init init_lapic_sysfs(void)
2726{
2727 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2728 if (boot_cpu_has(X86_FEATURE_APIC))
2729 register_syscore_ops(&lapic_syscore_ops);
2730
2731 return 0;
2732}
2733
2734/* local apic needs to resume before other devices access its registers. */
2735core_initcall(init_lapic_sysfs);
2736
2737#else /* CONFIG_PM */
2738
2739static void apic_pm_activate(void) { }
2740
2741#endif /* CONFIG_PM */
2742
2743#ifdef CONFIG_X86_64
2744
2745static int multi_checked;
2746static int multi;
2747
2748static int set_multi(const struct dmi_system_id *d)
2749{
2750 if (multi)
2751 return 0;
2752 pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
2753 multi = 1;
2754 return 0;
2755}
2756
2757static const struct dmi_system_id multi_dmi_table[] = {
2758 {
2759 .callback = set_multi,
2760 .ident = "IBM System Summit2",
2761 .matches = {
2762 DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2763 DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
2764 },
2765 },
2766 {}
2767};
2768
2769static void dmi_check_multi(void)
2770{
2771 if (multi_checked)
2772 return;
2773
2774 dmi_check_system(multi_dmi_table);
2775 multi_checked = 1;
2776}
2777
2778/*
2779 * apic_is_clustered_box() -- Check if we can expect good TSC
2780 *
2781 * Thus far, the major user of this is IBM's Summit2 series:
2782 * Clustered boxes may have unsynced TSC problems if they are
2783 * multi-chassis.
2784 * Use DMI to check them
2785 */
2786int apic_is_clustered_box(void)
2787{
2788 dmi_check_multi();
2789 return multi;
2790}
2791#endif
2792
2793/*
2794 * APIC command line parameters
2795 */
2796static int __init setup_disableapic(char *arg)
2797{
2798 disable_apic = 1;
2799 setup_clear_cpu_cap(X86_FEATURE_APIC);
2800 return 0;
2801}
2802early_param("disableapic", setup_disableapic);
2803
2804/* same as disableapic, for compatibility */
2805static int __init setup_nolapic(char *arg)
2806{
2807 return setup_disableapic(arg);
2808}
2809early_param("nolapic", setup_nolapic);
2810
2811static int __init parse_lapic_timer_c2_ok(char *arg)
2812{
2813 local_apic_timer_c2_ok = 1;
2814 return 0;
2815}
2816early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2817
2818static int __init parse_disable_apic_timer(char *arg)
2819{
2820 disable_apic_timer = 1;
2821 return 0;
2822}
2823early_param("noapictimer", parse_disable_apic_timer);
2824
2825static int __init parse_nolapic_timer(char *arg)
2826{
2827 disable_apic_timer = 1;
2828 return 0;
2829}
2830early_param("nolapic_timer", parse_nolapic_timer);
2831
2832static int __init apic_set_verbosity(char *arg)
2833{
2834 if (!arg) {
2835#ifdef CONFIG_X86_64
2836 skip_ioapic_setup = 0;
2837 return 0;
2838#endif
2839 return -EINVAL;
2840 }
2841
2842 if (strcmp("debug", arg) == 0)
2843 apic_verbosity = APIC_DEBUG;
2844 else if (strcmp("verbose", arg) == 0)
2845 apic_verbosity = APIC_VERBOSE;
2846#ifdef CONFIG_X86_64
2847 else {
2848 pr_warning("APIC Verbosity level %s not recognised"
2849 " use apic=verbose or apic=debug\n", arg);
2850 return -EINVAL;
2851 }
2852#endif
2853
2854 return 0;
2855}
2856early_param("apic", apic_set_verbosity);
2857
2858static int __init lapic_insert_resource(void)
2859{
2860 if (!apic_phys)
2861 return -1;
2862
2863 /* Put local APIC into the resource map. */
2864 lapic_resource.start = apic_phys;
2865 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2866 insert_resource(&iomem_resource, &lapic_resource);
2867
2868 return 0;
2869}
2870
2871/*
2872 * need call insert after e820__reserve_resources()
2873 * that is using request_resource
2874 */
2875late_initcall(lapic_insert_resource);
2876
2877static int __init apic_set_disabled_cpu_apicid(char *arg)
2878{
2879 if (!arg || !get_option(&arg, &disabled_cpu_apicid))
2880 return -EINVAL;
2881
2882 return 0;
2883}
2884early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid);
2885
2886static int __init apic_set_extnmi(char *arg)
2887{
2888 if (!arg)
2889 return -EINVAL;
2890
2891 if (!strncmp("all", arg, 3))
2892 apic_extnmi = APIC_EXTNMI_ALL;
2893 else if (!strncmp("none", arg, 4))
2894 apic_extnmi = APIC_EXTNMI_NONE;
2895 else if (!strncmp("bsp", arg, 3))
2896 apic_extnmi = APIC_EXTNMI_BSP;
2897 else {
2898 pr_warn("Unknown external NMI delivery mode `%s' ignored\n", arg);
2899 return -EINVAL;
2900 }
2901
2902 return 0;
2903}
2904early_param("apic_extnmi", apic_set_extnmi);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Local APIC handling, local APIC timers
4 *
5 * (c) 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
6 *
7 * Fixes
8 * Maciej W. Rozycki : Bits for genuine 82489DX APICs;
9 * thanks to Eric Gilmore
10 * and Rolf G. Tews
11 * for testing these extensively.
12 * Maciej W. Rozycki : Various updates and fixes.
13 * Mikael Pettersson : Power Management for UP-APIC.
14 * Pavel Machek and
15 * Mikael Pettersson : PM converted to driver model.
16 */
17
18#include <linux/perf_event.h>
19#include <linux/kernel_stat.h>
20#include <linux/mc146818rtc.h>
21#include <linux/acpi_pmtmr.h>
22#include <linux/clockchips.h>
23#include <linux/interrupt.h>
24#include <linux/memblock.h>
25#include <linux/ftrace.h>
26#include <linux/ioport.h>
27#include <linux/export.h>
28#include <linux/syscore_ops.h>
29#include <linux/delay.h>
30#include <linux/timex.h>
31#include <linux/i8253.h>
32#include <linux/dmar.h>
33#include <linux/init.h>
34#include <linux/cpu.h>
35#include <linux/dmi.h>
36#include <linux/smp.h>
37#include <linux/mm.h>
38
39#include <xen/xen.h>
40
41#include <asm/trace/irq_vectors.h>
42#include <asm/irq_remapping.h>
43#include <asm/pc-conf-reg.h>
44#include <asm/perf_event.h>
45#include <asm/x86_init.h>
46#include <linux/atomic.h>
47#include <asm/barrier.h>
48#include <asm/mpspec.h>
49#include <asm/i8259.h>
50#include <asm/proto.h>
51#include <asm/traps.h>
52#include <asm/apic.h>
53#include <asm/acpi.h>
54#include <asm/io_apic.h>
55#include <asm/desc.h>
56#include <asm/hpet.h>
57#include <asm/mtrr.h>
58#include <asm/time.h>
59#include <asm/smp.h>
60#include <asm/mce.h>
61#include <asm/tsc.h>
62#include <asm/hypervisor.h>
63#include <asm/cpu_device_id.h>
64#include <asm/intel-family.h>
65#include <asm/irq_regs.h>
66#include <asm/cpu.h>
67
68#include "local.h"
69
70unsigned int num_processors;
71
72unsigned disabled_cpus;
73
74/* Processor that is doing the boot up */
75u32 boot_cpu_physical_apicid __ro_after_init = BAD_APICID;
76EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid);
77
78u8 boot_cpu_apic_version __ro_after_init;
79
80/*
81 * Bitmask of physically existing CPUs:
82 */
83physid_mask_t phys_cpu_present_map;
84
85/*
86 * Processor to be disabled specified by kernel parameter
87 * disable_cpu_apicid=<int>, mostly used for the kdump 2nd kernel to
88 * avoid undefined behaviour caused by sending INIT from AP to BSP.
89 */
90static u32 disabled_cpu_apicid __ro_after_init = BAD_APICID;
91
92/*
93 * This variable controls which CPUs receive external NMIs. By default,
94 * external NMIs are delivered only to the BSP.
95 */
96static int apic_extnmi __ro_after_init = APIC_EXTNMI_BSP;
97
98/*
99 * Hypervisor supports 15 bits of APIC ID in MSI Extended Destination ID
100 */
101static bool virt_ext_dest_id __ro_after_init;
102
103/* For parallel bootup. */
104unsigned long apic_mmio_base __ro_after_init;
105
106static inline bool apic_accessible(void)
107{
108 return x2apic_mode || apic_mmio_base;
109}
110
111/*
112 * Map cpu index to physical APIC ID
113 */
114DEFINE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_apicid, BAD_APICID);
115DEFINE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_acpiid, U32_MAX);
116EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
117EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_acpiid);
118
119#ifdef CONFIG_X86_32
120/* Local APIC was disabled by the BIOS and enabled by the kernel */
121static int enabled_via_apicbase __ro_after_init;
122
123/*
124 * Handle interrupt mode configuration register (IMCR).
125 * This register controls whether the interrupt signals
126 * that reach the BSP come from the master PIC or from the
127 * local APIC. Before entering Symmetric I/O Mode, either
128 * the BIOS or the operating system must switch out of
129 * PIC Mode by changing the IMCR.
130 */
131static inline void imcr_pic_to_apic(void)
132{
133 /* NMI and 8259 INTR go through APIC */
134 pc_conf_set(PC_CONF_MPS_IMCR, 0x01);
135}
136
137static inline void imcr_apic_to_pic(void)
138{
139 /* NMI and 8259 INTR go directly to BSP */
140 pc_conf_set(PC_CONF_MPS_IMCR, 0x00);
141}
142#endif
143
144/*
145 * Knob to control our willingness to enable the local APIC.
146 *
147 * +1=force-enable
148 */
149static int force_enable_local_apic __initdata;
150
151/*
152 * APIC command line parameters
153 */
154static int __init parse_lapic(char *arg)
155{
156 if (IS_ENABLED(CONFIG_X86_32) && !arg)
157 force_enable_local_apic = 1;
158 else if (arg && !strncmp(arg, "notscdeadline", 13))
159 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
160 return 0;
161}
162early_param("lapic", parse_lapic);
163
164#ifdef CONFIG_X86_64
165static int apic_calibrate_pmtmr __initdata;
166static __init int setup_apicpmtimer(char *s)
167{
168 apic_calibrate_pmtmr = 1;
169 notsc_setup(NULL);
170 return 1;
171}
172__setup("apicpmtimer", setup_apicpmtimer);
173#endif
174
175static unsigned long mp_lapic_addr __ro_after_init;
176bool apic_is_disabled __ro_after_init;
177/* Disable local APIC timer from the kernel commandline or via dmi quirk */
178static int disable_apic_timer __initdata;
179/* Local APIC timer works in C2 */
180int local_apic_timer_c2_ok __ro_after_init;
181EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
182
183/*
184 * Debug level, exported for io_apic.c
185 */
186int apic_verbosity __ro_after_init;
187
188int pic_mode __ro_after_init;
189
190/* Have we found an MP table */
191int smp_found_config __ro_after_init;
192
193static struct resource lapic_resource = {
194 .name = "Local APIC",
195 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
196};
197
198unsigned int lapic_timer_period = 0;
199
200static void apic_pm_activate(void);
201
202/*
203 * Get the LAPIC version
204 */
205static inline int lapic_get_version(void)
206{
207 return GET_APIC_VERSION(apic_read(APIC_LVR));
208}
209
210/*
211 * Check, if the APIC is integrated or a separate chip
212 */
213static inline int lapic_is_integrated(void)
214{
215 return APIC_INTEGRATED(lapic_get_version());
216}
217
218/*
219 * Check, whether this is a modern or a first generation APIC
220 */
221static int modern_apic(void)
222{
223 /* AMD systems use old APIC versions, so check the CPU */
224 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
225 boot_cpu_data.x86 >= 0xf)
226 return 1;
227
228 /* Hygon systems use modern APIC */
229 if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
230 return 1;
231
232 return lapic_get_version() >= 0x14;
233}
234
235/*
236 * right after this call apic become NOOP driven
237 * so apic->write/read doesn't do anything
238 */
239static void __init apic_disable(void)
240{
241 apic_install_driver(&apic_noop);
242}
243
244void native_apic_icr_write(u32 low, u32 id)
245{
246 unsigned long flags;
247
248 local_irq_save(flags);
249 apic_write(APIC_ICR2, SET_XAPIC_DEST_FIELD(id));
250 apic_write(APIC_ICR, low);
251 local_irq_restore(flags);
252}
253
254u64 native_apic_icr_read(void)
255{
256 u32 icr1, icr2;
257
258 icr2 = apic_read(APIC_ICR2);
259 icr1 = apic_read(APIC_ICR);
260
261 return icr1 | ((u64)icr2 << 32);
262}
263
264#ifdef CONFIG_X86_32
265/**
266 * get_physical_broadcast - Get number of physical broadcast IDs
267 */
268int get_physical_broadcast(void)
269{
270 return modern_apic() ? 0xff : 0xf;
271}
272#endif
273
274/**
275 * lapic_get_maxlvt - get the maximum number of local vector table entries
276 */
277int lapic_get_maxlvt(void)
278{
279 /*
280 * - we always have APIC integrated on 64bit mode
281 * - 82489DXs do not report # of LVT entries
282 */
283 return lapic_is_integrated() ? GET_APIC_MAXLVT(apic_read(APIC_LVR)) : 2;
284}
285
286/*
287 * Local APIC timer
288 */
289
290/* Clock divisor */
291#define APIC_DIVISOR 16
292#define TSC_DIVISOR 8
293
294/* i82489DX specific */
295#define I82489DX_BASE_DIVIDER (((0x2) << 18))
296
297/*
298 * This function sets up the local APIC timer, with a timeout of
299 * 'clocks' APIC bus clock. During calibration we actually call
300 * this function twice on the boot CPU, once with a bogus timeout
301 * value, second time for real. The other (noncalibrating) CPUs
302 * call this function only once, with the real, calibrated value.
303 *
304 * We do reads before writes even if unnecessary, to get around the
305 * P5 APIC double write bug.
306 */
307static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
308{
309 unsigned int lvtt_value, tmp_value;
310
311 lvtt_value = LOCAL_TIMER_VECTOR;
312 if (!oneshot)
313 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
314 else if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
315 lvtt_value |= APIC_LVT_TIMER_TSCDEADLINE;
316
317 /*
318 * The i82489DX APIC uses bit 18 and 19 for the base divider. This
319 * overlaps with bit 18 on integrated APICs, but is not documented
320 * in the SDM. No problem though. i82489DX equipped systems do not
321 * have TSC deadline timer.
322 */
323 if (!lapic_is_integrated())
324 lvtt_value |= I82489DX_BASE_DIVIDER;
325
326 if (!irqen)
327 lvtt_value |= APIC_LVT_MASKED;
328
329 apic_write(APIC_LVTT, lvtt_value);
330
331 if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) {
332 /*
333 * See Intel SDM: TSC-Deadline Mode chapter. In xAPIC mode,
334 * writing to the APIC LVTT and TSC_DEADLINE MSR isn't serialized.
335 * According to Intel, MFENCE can do the serialization here.
336 */
337 asm volatile("mfence" : : : "memory");
338 return;
339 }
340
341 /*
342 * Divide PICLK by 16
343 */
344 tmp_value = apic_read(APIC_TDCR);
345 apic_write(APIC_TDCR,
346 (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
347 APIC_TDR_DIV_16);
348
349 if (!oneshot)
350 apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
351}
352
353/*
354 * Setup extended LVT, AMD specific
355 *
356 * Software should use the LVT offsets the BIOS provides. The offsets
357 * are determined by the subsystems using it like those for MCE
358 * threshold or IBS. On K8 only offset 0 (APIC500) and MCE interrupts
359 * are supported. Beginning with family 10h at least 4 offsets are
360 * available.
361 *
362 * Since the offsets must be consistent for all cores, we keep track
363 * of the LVT offsets in software and reserve the offset for the same
364 * vector also to be used on other cores. An offset is freed by
365 * setting the entry to APIC_EILVT_MASKED.
366 *
367 * If the BIOS is right, there should be no conflicts. Otherwise a
368 * "[Firmware Bug]: ..." error message is generated. However, if
369 * software does not properly determines the offsets, it is not
370 * necessarily a BIOS bug.
371 */
372
373static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX];
374
375static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new)
376{
377 return (old & APIC_EILVT_MASKED)
378 || (new == APIC_EILVT_MASKED)
379 || ((new & ~APIC_EILVT_MASKED) == old);
380}
381
382static unsigned int reserve_eilvt_offset(int offset, unsigned int new)
383{
384 unsigned int rsvd, vector;
385
386 if (offset >= APIC_EILVT_NR_MAX)
387 return ~0;
388
389 rsvd = atomic_read(&eilvt_offsets[offset]);
390 do {
391 vector = rsvd & ~APIC_EILVT_MASKED; /* 0: unassigned */
392 if (vector && !eilvt_entry_is_changeable(vector, new))
393 /* may not change if vectors are different */
394 return rsvd;
395 } while (!atomic_try_cmpxchg(&eilvt_offsets[offset], &rsvd, new));
396
397 rsvd = new & ~APIC_EILVT_MASKED;
398 if (rsvd && rsvd != vector)
399 pr_info("LVT offset %d assigned for vector 0x%02x\n",
400 offset, rsvd);
401
402 return new;
403}
404
405/*
406 * If mask=1, the LVT entry does not generate interrupts while mask=0
407 * enables the vector. See also the BKDGs. Must be called with
408 * preemption disabled.
409 */
410
411int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask)
412{
413 unsigned long reg = APIC_EILVTn(offset);
414 unsigned int new, old, reserved;
415
416 new = (mask << 16) | (msg_type << 8) | vector;
417 old = apic_read(reg);
418 reserved = reserve_eilvt_offset(offset, new);
419
420 if (reserved != new) {
421 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
422 "vector 0x%x, but the register is already in use for "
423 "vector 0x%x on another cpu\n",
424 smp_processor_id(), reg, offset, new, reserved);
425 return -EINVAL;
426 }
427
428 if (!eilvt_entry_is_changeable(old, new)) {
429 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
430 "vector 0x%x, but the register is already in use for "
431 "vector 0x%x on this cpu\n",
432 smp_processor_id(), reg, offset, new, old);
433 return -EBUSY;
434 }
435
436 apic_write(reg, new);
437
438 return 0;
439}
440EXPORT_SYMBOL_GPL(setup_APIC_eilvt);
441
442/*
443 * Program the next event, relative to now
444 */
445static int lapic_next_event(unsigned long delta,
446 struct clock_event_device *evt)
447{
448 apic_write(APIC_TMICT, delta);
449 return 0;
450}
451
452static int lapic_next_deadline(unsigned long delta,
453 struct clock_event_device *evt)
454{
455 u64 tsc;
456
457 /* This MSR is special and need a special fence: */
458 weak_wrmsr_fence();
459
460 tsc = rdtsc();
461 wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR));
462 return 0;
463}
464
465static int lapic_timer_shutdown(struct clock_event_device *evt)
466{
467 unsigned int v;
468
469 /* Lapic used as dummy for broadcast ? */
470 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
471 return 0;
472
473 v = apic_read(APIC_LVTT);
474 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
475 apic_write(APIC_LVTT, v);
476 apic_write(APIC_TMICT, 0);
477 return 0;
478}
479
480static inline int
481lapic_timer_set_periodic_oneshot(struct clock_event_device *evt, bool oneshot)
482{
483 /* Lapic used as dummy for broadcast ? */
484 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
485 return 0;
486
487 __setup_APIC_LVTT(lapic_timer_period, oneshot, 1);
488 return 0;
489}
490
491static int lapic_timer_set_periodic(struct clock_event_device *evt)
492{
493 return lapic_timer_set_periodic_oneshot(evt, false);
494}
495
496static int lapic_timer_set_oneshot(struct clock_event_device *evt)
497{
498 return lapic_timer_set_periodic_oneshot(evt, true);
499}
500
501/*
502 * Local APIC timer broadcast function
503 */
504static void lapic_timer_broadcast(const struct cpumask *mask)
505{
506#ifdef CONFIG_SMP
507 __apic_send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
508#endif
509}
510
511
512/*
513 * The local apic timer can be used for any function which is CPU local.
514 */
515static struct clock_event_device lapic_clockevent = {
516 .name = "lapic",
517 .features = CLOCK_EVT_FEAT_PERIODIC |
518 CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP
519 | CLOCK_EVT_FEAT_DUMMY,
520 .shift = 32,
521 .set_state_shutdown = lapic_timer_shutdown,
522 .set_state_periodic = lapic_timer_set_periodic,
523 .set_state_oneshot = lapic_timer_set_oneshot,
524 .set_state_oneshot_stopped = lapic_timer_shutdown,
525 .set_next_event = lapic_next_event,
526 .broadcast = lapic_timer_broadcast,
527 .rating = 100,
528 .irq = -1,
529};
530static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
531
532static const struct x86_cpu_id deadline_match[] __initconst = {
533 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(HASWELL_X, X86_STEPPINGS(0x2, 0x2), 0x3a), /* EP */
534 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(HASWELL_X, X86_STEPPINGS(0x4, 0x4), 0x0f), /* EX */
535
536 X86_MATCH_INTEL_FAM6_MODEL( BROADWELL_X, 0x0b000020),
537
538 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x2, 0x2), 0x00000011),
539 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x3, 0x3), 0x0700000e),
540 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x4, 0x4), 0x0f00000c),
541 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x5, 0x5), 0x0e000003),
542
543 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x3, 0x3), 0x01000136),
544 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x4, 0x4), 0x02000014),
545 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x5, 0xf), 0),
546
547 X86_MATCH_INTEL_FAM6_MODEL( HASWELL, 0x22),
548 X86_MATCH_INTEL_FAM6_MODEL( HASWELL_L, 0x20),
549 X86_MATCH_INTEL_FAM6_MODEL( HASWELL_G, 0x17),
550
551 X86_MATCH_INTEL_FAM6_MODEL( BROADWELL, 0x25),
552 X86_MATCH_INTEL_FAM6_MODEL( BROADWELL_G, 0x17),
553
554 X86_MATCH_INTEL_FAM6_MODEL( SKYLAKE_L, 0xb2),
555 X86_MATCH_INTEL_FAM6_MODEL( SKYLAKE, 0xb2),
556
557 X86_MATCH_INTEL_FAM6_MODEL( KABYLAKE_L, 0x52),
558 X86_MATCH_INTEL_FAM6_MODEL( KABYLAKE, 0x52),
559
560 {},
561};
562
563static __init bool apic_validate_deadline_timer(void)
564{
565 const struct x86_cpu_id *m;
566 u32 rev;
567
568 if (!boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
569 return false;
570 if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
571 return true;
572
573 m = x86_match_cpu(deadline_match);
574 if (!m)
575 return true;
576
577 rev = (u32)m->driver_data;
578
579 if (boot_cpu_data.microcode >= rev)
580 return true;
581
582 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
583 pr_err(FW_BUG "TSC_DEADLINE disabled due to Errata; "
584 "please update microcode to version: 0x%x (or later)\n", rev);
585 return false;
586}
587
588/*
589 * Setup the local APIC timer for this CPU. Copy the initialized values
590 * of the boot CPU and register the clock event in the framework.
591 */
592static void setup_APIC_timer(void)
593{
594 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
595
596 if (this_cpu_has(X86_FEATURE_ARAT)) {
597 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP;
598 /* Make LAPIC timer preferable over percpu HPET */
599 lapic_clockevent.rating = 150;
600 }
601
602 memcpy(levt, &lapic_clockevent, sizeof(*levt));
603 levt->cpumask = cpumask_of(smp_processor_id());
604
605 if (this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) {
606 levt->name = "lapic-deadline";
607 levt->features &= ~(CLOCK_EVT_FEAT_PERIODIC |
608 CLOCK_EVT_FEAT_DUMMY);
609 levt->set_next_event = lapic_next_deadline;
610 clockevents_config_and_register(levt,
611 tsc_khz * (1000 / TSC_DIVISOR),
612 0xF, ~0UL);
613 } else
614 clockevents_register_device(levt);
615}
616
617/*
618 * Install the updated TSC frequency from recalibration at the TSC
619 * deadline clockevent devices.
620 */
621static void __lapic_update_tsc_freq(void *info)
622{
623 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
624
625 if (!this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
626 return;
627
628 clockevents_update_freq(levt, tsc_khz * (1000 / TSC_DIVISOR));
629}
630
631void lapic_update_tsc_freq(void)
632{
633 /*
634 * The clockevent device's ->mult and ->shift can both be
635 * changed. In order to avoid races, schedule the frequency
636 * update code on each CPU.
637 */
638 on_each_cpu(__lapic_update_tsc_freq, NULL, 0);
639}
640
641/*
642 * In this functions we calibrate APIC bus clocks to the external timer.
643 *
644 * We want to do the calibration only once since we want to have local timer
645 * irqs synchronous. CPUs connected by the same APIC bus have the very same bus
646 * frequency.
647 *
648 * This was previously done by reading the PIT/HPET and waiting for a wrap
649 * around to find out, that a tick has elapsed. I have a box, where the PIT
650 * readout is broken, so it never gets out of the wait loop again. This was
651 * also reported by others.
652 *
653 * Monitoring the jiffies value is inaccurate and the clockevents
654 * infrastructure allows us to do a simple substitution of the interrupt
655 * handler.
656 *
657 * The calibration routine also uses the pm_timer when possible, as the PIT
658 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
659 * back to normal later in the boot process).
660 */
661
662#define LAPIC_CAL_LOOPS (HZ/10)
663
664static __initdata int lapic_cal_loops = -1;
665static __initdata long lapic_cal_t1, lapic_cal_t2;
666static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
667static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
668static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
669
670/*
671 * Temporary interrupt handler and polled calibration function.
672 */
673static void __init lapic_cal_handler(struct clock_event_device *dev)
674{
675 unsigned long long tsc = 0;
676 long tapic = apic_read(APIC_TMCCT);
677 unsigned long pm = acpi_pm_read_early();
678
679 if (boot_cpu_has(X86_FEATURE_TSC))
680 tsc = rdtsc();
681
682 switch (lapic_cal_loops++) {
683 case 0:
684 lapic_cal_t1 = tapic;
685 lapic_cal_tsc1 = tsc;
686 lapic_cal_pm1 = pm;
687 lapic_cal_j1 = jiffies;
688 break;
689
690 case LAPIC_CAL_LOOPS:
691 lapic_cal_t2 = tapic;
692 lapic_cal_tsc2 = tsc;
693 if (pm < lapic_cal_pm1)
694 pm += ACPI_PM_OVRRUN;
695 lapic_cal_pm2 = pm;
696 lapic_cal_j2 = jiffies;
697 break;
698 }
699}
700
701static int __init
702calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc)
703{
704 const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
705 const long pm_thresh = pm_100ms / 100;
706 unsigned long mult;
707 u64 res;
708
709#ifndef CONFIG_X86_PM_TIMER
710 return -1;
711#endif
712
713 apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm);
714
715 /* Check, if the PM timer is available */
716 if (!deltapm)
717 return -1;
718
719 mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
720
721 if (deltapm > (pm_100ms - pm_thresh) &&
722 deltapm < (pm_100ms + pm_thresh)) {
723 apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n");
724 return 0;
725 }
726
727 res = (((u64)deltapm) * mult) >> 22;
728 do_div(res, 1000000);
729 pr_warn("APIC calibration not consistent "
730 "with PM-Timer: %ldms instead of 100ms\n", (long)res);
731
732 /* Correct the lapic counter value */
733 res = (((u64)(*delta)) * pm_100ms);
734 do_div(res, deltapm);
735 pr_info("APIC delta adjusted to PM-Timer: "
736 "%lu (%ld)\n", (unsigned long)res, *delta);
737 *delta = (long)res;
738
739 /* Correct the tsc counter value */
740 if (boot_cpu_has(X86_FEATURE_TSC)) {
741 res = (((u64)(*deltatsc)) * pm_100ms);
742 do_div(res, deltapm);
743 apic_printk(APIC_VERBOSE, "TSC delta adjusted to "
744 "PM-Timer: %lu (%ld)\n",
745 (unsigned long)res, *deltatsc);
746 *deltatsc = (long)res;
747 }
748
749 return 0;
750}
751
752static int __init lapic_init_clockevent(void)
753{
754 if (!lapic_timer_period)
755 return -1;
756
757 /* Calculate the scaled math multiplication factor */
758 lapic_clockevent.mult = div_sc(lapic_timer_period/APIC_DIVISOR,
759 TICK_NSEC, lapic_clockevent.shift);
760 lapic_clockevent.max_delta_ns =
761 clockevent_delta2ns(0x7FFFFFFF, &lapic_clockevent);
762 lapic_clockevent.max_delta_ticks = 0x7FFFFFFF;
763 lapic_clockevent.min_delta_ns =
764 clockevent_delta2ns(0xF, &lapic_clockevent);
765 lapic_clockevent.min_delta_ticks = 0xF;
766
767 return 0;
768}
769
770bool __init apic_needs_pit(void)
771{
772 /*
773 * If the frequencies are not known, PIT is required for both TSC
774 * and apic timer calibration.
775 */
776 if (!tsc_khz || !cpu_khz)
777 return true;
778
779 /* Is there an APIC at all or is it disabled? */
780 if (!boot_cpu_has(X86_FEATURE_APIC) || apic_is_disabled)
781 return true;
782
783 /*
784 * If interrupt delivery mode is legacy PIC or virtual wire without
785 * configuration, the local APIC timer won't be set up. Make sure
786 * that the PIT is initialized.
787 */
788 if (apic_intr_mode == APIC_PIC ||
789 apic_intr_mode == APIC_VIRTUAL_WIRE_NO_CONFIG)
790 return true;
791
792 /* Virt guests may lack ARAT, but still have DEADLINE */
793 if (!boot_cpu_has(X86_FEATURE_ARAT))
794 return true;
795
796 /* Deadline timer is based on TSC so no further PIT action required */
797 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
798 return false;
799
800 /* APIC timer disabled? */
801 if (disable_apic_timer)
802 return true;
803 /*
804 * The APIC timer frequency is known already, no PIT calibration
805 * required. If unknown, let the PIT be initialized.
806 */
807 return lapic_timer_period == 0;
808}
809
810static int __init calibrate_APIC_clock(void)
811{
812 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
813 u64 tsc_perj = 0, tsc_start = 0;
814 unsigned long jif_start;
815 unsigned long deltaj;
816 long delta, deltatsc;
817 int pm_referenced = 0;
818
819 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
820 return 0;
821
822 /*
823 * Check if lapic timer has already been calibrated by platform
824 * specific routine, such as tsc calibration code. If so just fill
825 * in the clockevent structure and return.
826 */
827 if (!lapic_init_clockevent()) {
828 apic_printk(APIC_VERBOSE, "lapic timer already calibrated %d\n",
829 lapic_timer_period);
830 /*
831 * Direct calibration methods must have an always running
832 * local APIC timer, no need for broadcast timer.
833 */
834 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
835 return 0;
836 }
837
838 apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
839 "calibrating APIC timer ...\n");
840
841 /*
842 * There are platforms w/o global clockevent devices. Instead of
843 * making the calibration conditional on that, use a polling based
844 * approach everywhere.
845 */
846 local_irq_disable();
847
848 /*
849 * Setup the APIC counter to maximum. There is no way the lapic
850 * can underflow in the 100ms detection time frame
851 */
852 __setup_APIC_LVTT(0xffffffff, 0, 0);
853
854 /*
855 * Methods to terminate the calibration loop:
856 * 1) Global clockevent if available (jiffies)
857 * 2) TSC if available and frequency is known
858 */
859 jif_start = READ_ONCE(jiffies);
860
861 if (tsc_khz) {
862 tsc_start = rdtsc();
863 tsc_perj = div_u64((u64)tsc_khz * 1000, HZ);
864 }
865
866 /*
867 * Enable interrupts so the tick can fire, if a global
868 * clockevent device is available
869 */
870 local_irq_enable();
871
872 while (lapic_cal_loops <= LAPIC_CAL_LOOPS) {
873 /* Wait for a tick to elapse */
874 while (1) {
875 if (tsc_khz) {
876 u64 tsc_now = rdtsc();
877 if ((tsc_now - tsc_start) >= tsc_perj) {
878 tsc_start += tsc_perj;
879 break;
880 }
881 } else {
882 unsigned long jif_now = READ_ONCE(jiffies);
883
884 if (time_after(jif_now, jif_start)) {
885 jif_start = jif_now;
886 break;
887 }
888 }
889 cpu_relax();
890 }
891
892 /* Invoke the calibration routine */
893 local_irq_disable();
894 lapic_cal_handler(NULL);
895 local_irq_enable();
896 }
897
898 local_irq_disable();
899
900 /* Build delta t1-t2 as apic timer counts down */
901 delta = lapic_cal_t1 - lapic_cal_t2;
902 apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
903
904 deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
905
906 /* we trust the PM based calibration if possible */
907 pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
908 &delta, &deltatsc);
909
910 lapic_timer_period = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
911 lapic_init_clockevent();
912
913 apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
914 apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult);
915 apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
916 lapic_timer_period);
917
918 if (boot_cpu_has(X86_FEATURE_TSC)) {
919 apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
920 "%ld.%04ld MHz.\n",
921 (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
922 (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
923 }
924
925 apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
926 "%u.%04u MHz.\n",
927 lapic_timer_period / (1000000 / HZ),
928 lapic_timer_period % (1000000 / HZ));
929
930 /*
931 * Do a sanity check on the APIC calibration result
932 */
933 if (lapic_timer_period < (1000000 / HZ)) {
934 local_irq_enable();
935 pr_warn("APIC frequency too slow, disabling apic timer\n");
936 return -1;
937 }
938
939 levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
940
941 /*
942 * PM timer calibration failed or not turned on so lets try APIC
943 * timer based calibration, if a global clockevent device is
944 * available.
945 */
946 if (!pm_referenced && global_clock_event) {
947 apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
948
949 /*
950 * Setup the apic timer manually
951 */
952 levt->event_handler = lapic_cal_handler;
953 lapic_timer_set_periodic(levt);
954 lapic_cal_loops = -1;
955
956 /* Let the interrupts run */
957 local_irq_enable();
958
959 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
960 cpu_relax();
961
962 /* Stop the lapic timer */
963 local_irq_disable();
964 lapic_timer_shutdown(levt);
965
966 /* Jiffies delta */
967 deltaj = lapic_cal_j2 - lapic_cal_j1;
968 apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
969
970 /* Check, if the jiffies result is consistent */
971 if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
972 apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
973 else
974 levt->features |= CLOCK_EVT_FEAT_DUMMY;
975 }
976 local_irq_enable();
977
978 if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
979 pr_warn("APIC timer disabled due to verification failure\n");
980 return -1;
981 }
982
983 return 0;
984}
985
986/*
987 * Setup the boot APIC
988 *
989 * Calibrate and verify the result.
990 */
991void __init setup_boot_APIC_clock(void)
992{
993 /*
994 * The local apic timer can be disabled via the kernel
995 * commandline or from the CPU detection code. Register the lapic
996 * timer as a dummy clock event source on SMP systems, so the
997 * broadcast mechanism is used. On UP systems simply ignore it.
998 */
999 if (disable_apic_timer) {
1000 pr_info("Disabling APIC timer\n");
1001 /* No broadcast on UP ! */
1002 if (num_possible_cpus() > 1) {
1003 lapic_clockevent.mult = 1;
1004 setup_APIC_timer();
1005 }
1006 return;
1007 }
1008
1009 if (calibrate_APIC_clock()) {
1010 /* No broadcast on UP ! */
1011 if (num_possible_cpus() > 1)
1012 setup_APIC_timer();
1013 return;
1014 }
1015
1016 /*
1017 * If nmi_watchdog is set to IO_APIC, we need the
1018 * PIT/HPET going. Otherwise register lapic as a dummy
1019 * device.
1020 */
1021 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
1022
1023 /* Setup the lapic or request the broadcast */
1024 setup_APIC_timer();
1025 amd_e400_c1e_apic_setup();
1026}
1027
1028void setup_secondary_APIC_clock(void)
1029{
1030 setup_APIC_timer();
1031 amd_e400_c1e_apic_setup();
1032}
1033
1034/*
1035 * The guts of the apic timer interrupt
1036 */
1037static void local_apic_timer_interrupt(void)
1038{
1039 struct clock_event_device *evt = this_cpu_ptr(&lapic_events);
1040
1041 /*
1042 * Normally we should not be here till LAPIC has been initialized but
1043 * in some cases like kdump, its possible that there is a pending LAPIC
1044 * timer interrupt from previous kernel's context and is delivered in
1045 * new kernel the moment interrupts are enabled.
1046 *
1047 * Interrupts are enabled early and LAPIC is setup much later, hence
1048 * its possible that when we get here evt->event_handler is NULL.
1049 * Check for event_handler being NULL and discard the interrupt as
1050 * spurious.
1051 */
1052 if (!evt->event_handler) {
1053 pr_warn("Spurious LAPIC timer interrupt on cpu %d\n",
1054 smp_processor_id());
1055 /* Switch it off */
1056 lapic_timer_shutdown(evt);
1057 return;
1058 }
1059
1060 /*
1061 * the NMI deadlock-detector uses this.
1062 */
1063 inc_irq_stat(apic_timer_irqs);
1064
1065 evt->event_handler(evt);
1066}
1067
1068/*
1069 * Local APIC timer interrupt. This is the most natural way for doing
1070 * local interrupts, but local timer interrupts can be emulated by
1071 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
1072 *
1073 * [ if a single-CPU system runs an SMP kernel then we call the local
1074 * interrupt as well. Thus we cannot inline the local irq ... ]
1075 */
1076DEFINE_IDTENTRY_SYSVEC(sysvec_apic_timer_interrupt)
1077{
1078 struct pt_regs *old_regs = set_irq_regs(regs);
1079
1080 apic_eoi();
1081 trace_local_timer_entry(LOCAL_TIMER_VECTOR);
1082 local_apic_timer_interrupt();
1083 trace_local_timer_exit(LOCAL_TIMER_VECTOR);
1084
1085 set_irq_regs(old_regs);
1086}
1087
1088/*
1089 * Local APIC start and shutdown
1090 */
1091
1092/**
1093 * clear_local_APIC - shutdown the local APIC
1094 *
1095 * This is called, when a CPU is disabled and before rebooting, so the state of
1096 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
1097 * leftovers during boot.
1098 */
1099void clear_local_APIC(void)
1100{
1101 int maxlvt;
1102 u32 v;
1103
1104 if (!apic_accessible())
1105 return;
1106
1107 maxlvt = lapic_get_maxlvt();
1108 /*
1109 * Masking an LVT entry can trigger a local APIC error
1110 * if the vector is zero. Mask LVTERR first to prevent this.
1111 */
1112 if (maxlvt >= 3) {
1113 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
1114 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
1115 }
1116 /*
1117 * Careful: we have to set masks only first to deassert
1118 * any level-triggered sources.
1119 */
1120 v = apic_read(APIC_LVTT);
1121 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
1122 v = apic_read(APIC_LVT0);
1123 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
1124 v = apic_read(APIC_LVT1);
1125 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
1126 if (maxlvt >= 4) {
1127 v = apic_read(APIC_LVTPC);
1128 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
1129 }
1130
1131 /* lets not touch this if we didn't frob it */
1132#ifdef CONFIG_X86_THERMAL_VECTOR
1133 if (maxlvt >= 5) {
1134 v = apic_read(APIC_LVTTHMR);
1135 apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
1136 }
1137#endif
1138#ifdef CONFIG_X86_MCE_INTEL
1139 if (maxlvt >= 6) {
1140 v = apic_read(APIC_LVTCMCI);
1141 if (!(v & APIC_LVT_MASKED))
1142 apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED);
1143 }
1144#endif
1145
1146 /*
1147 * Clean APIC state for other OSs:
1148 */
1149 apic_write(APIC_LVTT, APIC_LVT_MASKED);
1150 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1151 apic_write(APIC_LVT1, APIC_LVT_MASKED);
1152 if (maxlvt >= 3)
1153 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
1154 if (maxlvt >= 4)
1155 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
1156
1157 /* Integrated APIC (!82489DX) ? */
1158 if (lapic_is_integrated()) {
1159 if (maxlvt > 3)
1160 /* Clear ESR due to Pentium errata 3AP and 11AP */
1161 apic_write(APIC_ESR, 0);
1162 apic_read(APIC_ESR);
1163 }
1164}
1165
1166/**
1167 * apic_soft_disable - Clears and software disables the local APIC on hotplug
1168 *
1169 * Contrary to disable_local_APIC() this does not touch the enable bit in
1170 * MSR_IA32_APICBASE. Clearing that bit on systems based on the 3 wire APIC
1171 * bus would require a hardware reset as the APIC would lose track of bus
1172 * arbitration. On systems with FSB delivery APICBASE could be disabled,
1173 * but it has to be guaranteed that no interrupt is sent to the APIC while
1174 * in that state and it's not clear from the SDM whether it still responds
1175 * to INIT/SIPI messages. Stay on the safe side and use software disable.
1176 */
1177void apic_soft_disable(void)
1178{
1179 u32 value;
1180
1181 clear_local_APIC();
1182
1183 /* Soft disable APIC (implies clearing of registers for 82489DX!). */
1184 value = apic_read(APIC_SPIV);
1185 value &= ~APIC_SPIV_APIC_ENABLED;
1186 apic_write(APIC_SPIV, value);
1187}
1188
1189/**
1190 * disable_local_APIC - clear and disable the local APIC
1191 */
1192void disable_local_APIC(void)
1193{
1194 if (!apic_accessible())
1195 return;
1196
1197 apic_soft_disable();
1198
1199#ifdef CONFIG_X86_32
1200 /*
1201 * When LAPIC was disabled by the BIOS and enabled by the kernel,
1202 * restore the disabled state.
1203 */
1204 if (enabled_via_apicbase) {
1205 unsigned int l, h;
1206
1207 rdmsr(MSR_IA32_APICBASE, l, h);
1208 l &= ~MSR_IA32_APICBASE_ENABLE;
1209 wrmsr(MSR_IA32_APICBASE, l, h);
1210 }
1211#endif
1212}
1213
1214/*
1215 * If Linux enabled the LAPIC against the BIOS default disable it down before
1216 * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
1217 * not power-off. Additionally clear all LVT entries before disable_local_APIC
1218 * for the case where Linux didn't enable the LAPIC.
1219 */
1220void lapic_shutdown(void)
1221{
1222 unsigned long flags;
1223
1224 if (!boot_cpu_has(X86_FEATURE_APIC) && !apic_from_smp_config())
1225 return;
1226
1227 local_irq_save(flags);
1228
1229#ifdef CONFIG_X86_32
1230 if (!enabled_via_apicbase)
1231 clear_local_APIC();
1232 else
1233#endif
1234 disable_local_APIC();
1235
1236
1237 local_irq_restore(flags);
1238}
1239
1240/**
1241 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1242 */
1243void __init sync_Arb_IDs(void)
1244{
1245 /*
1246 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1247 * needed on AMD.
1248 */
1249 if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1250 return;
1251
1252 /*
1253 * Wait for idle.
1254 */
1255 apic_wait_icr_idle();
1256
1257 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1258 apic_write(APIC_ICR, APIC_DEST_ALLINC |
1259 APIC_INT_LEVELTRIG | APIC_DM_INIT);
1260}
1261
1262enum apic_intr_mode_id apic_intr_mode __ro_after_init;
1263
1264static int __init __apic_intr_mode_select(void)
1265{
1266 /* Check kernel option */
1267 if (apic_is_disabled) {
1268 pr_info("APIC disabled via kernel command line\n");
1269 return APIC_PIC;
1270 }
1271
1272 /* Check BIOS */
1273#ifdef CONFIG_X86_64
1274 /* On 64-bit, the APIC must be integrated, Check local APIC only */
1275 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1276 apic_is_disabled = true;
1277 pr_info("APIC disabled by BIOS\n");
1278 return APIC_PIC;
1279 }
1280#else
1281 /* On 32-bit, the APIC may be integrated APIC or 82489DX */
1282
1283 /* Neither 82489DX nor integrated APIC ? */
1284 if (!boot_cpu_has(X86_FEATURE_APIC) && !smp_found_config) {
1285 apic_is_disabled = true;
1286 return APIC_PIC;
1287 }
1288
1289 /* If the BIOS pretends there is an integrated APIC ? */
1290 if (!boot_cpu_has(X86_FEATURE_APIC) &&
1291 APIC_INTEGRATED(boot_cpu_apic_version)) {
1292 apic_is_disabled = true;
1293 pr_err(FW_BUG "Local APIC not detected, force emulation\n");
1294 return APIC_PIC;
1295 }
1296#endif
1297
1298 /* Check MP table or ACPI MADT configuration */
1299 if (!smp_found_config) {
1300 disable_ioapic_support();
1301 if (!acpi_lapic) {
1302 pr_info("APIC: ACPI MADT or MP tables are not detected\n");
1303 return APIC_VIRTUAL_WIRE_NO_CONFIG;
1304 }
1305 return APIC_VIRTUAL_WIRE;
1306 }
1307
1308#ifdef CONFIG_SMP
1309 /* If SMP should be disabled, then really disable it! */
1310 if (!setup_max_cpus) {
1311 pr_info("APIC: SMP mode deactivated\n");
1312 return APIC_SYMMETRIC_IO_NO_ROUTING;
1313 }
1314#endif
1315
1316 return APIC_SYMMETRIC_IO;
1317}
1318
1319/* Select the interrupt delivery mode for the BSP */
1320void __init apic_intr_mode_select(void)
1321{
1322 apic_intr_mode = __apic_intr_mode_select();
1323}
1324
1325/*
1326 * An initial setup of the virtual wire mode.
1327 */
1328void __init init_bsp_APIC(void)
1329{
1330 unsigned int value;
1331
1332 /*
1333 * Don't do the setup now if we have a SMP BIOS as the
1334 * through-I/O-APIC virtual wire mode might be active.
1335 */
1336 if (smp_found_config || !boot_cpu_has(X86_FEATURE_APIC))
1337 return;
1338
1339 /*
1340 * Do not trust the local APIC being empty at bootup.
1341 */
1342 clear_local_APIC();
1343
1344 /*
1345 * Enable APIC.
1346 */
1347 value = apic_read(APIC_SPIV);
1348 value &= ~APIC_VECTOR_MASK;
1349 value |= APIC_SPIV_APIC_ENABLED;
1350
1351#ifdef CONFIG_X86_32
1352 /* This bit is reserved on P4/Xeon and should be cleared */
1353 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1354 (boot_cpu_data.x86 == 15))
1355 value &= ~APIC_SPIV_FOCUS_DISABLED;
1356 else
1357#endif
1358 value |= APIC_SPIV_FOCUS_DISABLED;
1359 value |= SPURIOUS_APIC_VECTOR;
1360 apic_write(APIC_SPIV, value);
1361
1362 /*
1363 * Set up the virtual wire mode.
1364 */
1365 apic_write(APIC_LVT0, APIC_DM_EXTINT);
1366 value = APIC_DM_NMI;
1367 if (!lapic_is_integrated()) /* 82489DX */
1368 value |= APIC_LVT_LEVEL_TRIGGER;
1369 if (apic_extnmi == APIC_EXTNMI_NONE)
1370 value |= APIC_LVT_MASKED;
1371 apic_write(APIC_LVT1, value);
1372}
1373
1374static void __init apic_bsp_setup(bool upmode);
1375
1376/* Init the interrupt delivery mode for the BSP */
1377void __init apic_intr_mode_init(void)
1378{
1379 bool upmode = IS_ENABLED(CONFIG_UP_LATE_INIT);
1380
1381 switch (apic_intr_mode) {
1382 case APIC_PIC:
1383 pr_info("APIC: Keep in PIC mode(8259)\n");
1384 return;
1385 case APIC_VIRTUAL_WIRE:
1386 pr_info("APIC: Switch to virtual wire mode setup\n");
1387 break;
1388 case APIC_VIRTUAL_WIRE_NO_CONFIG:
1389 pr_info("APIC: Switch to virtual wire mode setup with no configuration\n");
1390 upmode = true;
1391 break;
1392 case APIC_SYMMETRIC_IO:
1393 pr_info("APIC: Switch to symmetric I/O mode setup\n");
1394 break;
1395 case APIC_SYMMETRIC_IO_NO_ROUTING:
1396 pr_info("APIC: Switch to symmetric I/O mode setup in no SMP routine\n");
1397 break;
1398 }
1399
1400 x86_64_probe_apic();
1401
1402 x86_32_install_bigsmp();
1403
1404 if (x86_platform.apic_post_init)
1405 x86_platform.apic_post_init();
1406
1407 apic_bsp_setup(upmode);
1408}
1409
1410static void lapic_setup_esr(void)
1411{
1412 unsigned int oldvalue, value, maxlvt;
1413
1414 if (!lapic_is_integrated()) {
1415 pr_info("No ESR for 82489DX.\n");
1416 return;
1417 }
1418
1419 if (apic->disable_esr) {
1420 /*
1421 * Something untraceable is creating bad interrupts on
1422 * secondary quads ... for the moment, just leave the
1423 * ESR disabled - we can't do anything useful with the
1424 * errors anyway - mbligh
1425 */
1426 pr_info("Leaving ESR disabled.\n");
1427 return;
1428 }
1429
1430 maxlvt = lapic_get_maxlvt();
1431 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
1432 apic_write(APIC_ESR, 0);
1433 oldvalue = apic_read(APIC_ESR);
1434
1435 /* enables sending errors */
1436 value = ERROR_APIC_VECTOR;
1437 apic_write(APIC_LVTERR, value);
1438
1439 /*
1440 * spec says clear errors after enabling vector.
1441 */
1442 if (maxlvt > 3)
1443 apic_write(APIC_ESR, 0);
1444 value = apic_read(APIC_ESR);
1445 if (value != oldvalue)
1446 apic_printk(APIC_VERBOSE, "ESR value before enabling "
1447 "vector: 0x%08x after: 0x%08x\n",
1448 oldvalue, value);
1449}
1450
1451#define APIC_IR_REGS APIC_ISR_NR
1452#define APIC_IR_BITS (APIC_IR_REGS * 32)
1453#define APIC_IR_MAPSIZE (APIC_IR_BITS / BITS_PER_LONG)
1454
1455union apic_ir {
1456 unsigned long map[APIC_IR_MAPSIZE];
1457 u32 regs[APIC_IR_REGS];
1458};
1459
1460static bool apic_check_and_ack(union apic_ir *irr, union apic_ir *isr)
1461{
1462 int i, bit;
1463
1464 /* Read the IRRs */
1465 for (i = 0; i < APIC_IR_REGS; i++)
1466 irr->regs[i] = apic_read(APIC_IRR + i * 0x10);
1467
1468 /* Read the ISRs */
1469 for (i = 0; i < APIC_IR_REGS; i++)
1470 isr->regs[i] = apic_read(APIC_ISR + i * 0x10);
1471
1472 /*
1473 * If the ISR map is not empty. ACK the APIC and run another round
1474 * to verify whether a pending IRR has been unblocked and turned
1475 * into a ISR.
1476 */
1477 if (!bitmap_empty(isr->map, APIC_IR_BITS)) {
1478 /*
1479 * There can be multiple ISR bits set when a high priority
1480 * interrupt preempted a lower priority one. Issue an ACK
1481 * per set bit.
1482 */
1483 for_each_set_bit(bit, isr->map, APIC_IR_BITS)
1484 apic_eoi();
1485 return true;
1486 }
1487
1488 return !bitmap_empty(irr->map, APIC_IR_BITS);
1489}
1490
1491/*
1492 * After a crash, we no longer service the interrupts and a pending
1493 * interrupt from previous kernel might still have ISR bit set.
1494 *
1495 * Most probably by now the CPU has serviced that pending interrupt and it
1496 * might not have done the apic_eoi() because it thought, interrupt
1497 * came from i8259 as ExtInt. LAPIC did not get EOI so it does not clear
1498 * the ISR bit and cpu thinks it has already serviced the interrupt. Hence
1499 * a vector might get locked. It was noticed for timer irq (vector
1500 * 0x31). Issue an extra EOI to clear ISR.
1501 *
1502 * If there are pending IRR bits they turn into ISR bits after a higher
1503 * priority ISR bit has been acked.
1504 */
1505static void apic_pending_intr_clear(void)
1506{
1507 union apic_ir irr, isr;
1508 unsigned int i;
1509
1510 /* 512 loops are way oversized and give the APIC a chance to obey. */
1511 for (i = 0; i < 512; i++) {
1512 if (!apic_check_and_ack(&irr, &isr))
1513 return;
1514 }
1515 /* Dump the IRR/ISR content if that failed */
1516 pr_warn("APIC: Stale IRR: %256pb ISR: %256pb\n", irr.map, isr.map);
1517}
1518
1519/**
1520 * setup_local_APIC - setup the local APIC
1521 *
1522 * Used to setup local APIC while initializing BSP or bringing up APs.
1523 * Always called with preemption disabled.
1524 */
1525static void setup_local_APIC(void)
1526{
1527 int cpu = smp_processor_id();
1528 unsigned int value;
1529
1530 if (apic_is_disabled) {
1531 disable_ioapic_support();
1532 return;
1533 }
1534
1535 /*
1536 * If this comes from kexec/kcrash the APIC might be enabled in
1537 * SPIV. Soft disable it before doing further initialization.
1538 */
1539 value = apic_read(APIC_SPIV);
1540 value &= ~APIC_SPIV_APIC_ENABLED;
1541 apic_write(APIC_SPIV, value);
1542
1543#ifdef CONFIG_X86_32
1544 /* Pound the ESR really hard over the head with a big hammer - mbligh */
1545 if (lapic_is_integrated() && apic->disable_esr) {
1546 apic_write(APIC_ESR, 0);
1547 apic_write(APIC_ESR, 0);
1548 apic_write(APIC_ESR, 0);
1549 apic_write(APIC_ESR, 0);
1550 }
1551#endif
1552 /* Validate that the APIC is registered if required */
1553 BUG_ON(apic->apic_id_registered && !apic->apic_id_registered());
1554
1555 /*
1556 * Intel recommends to set DFR, LDR and TPR before enabling
1557 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
1558 * document number 292116).
1559 *
1560 * Except for APICs which operate in physical destination mode.
1561 */
1562 if (apic->init_apic_ldr)
1563 apic->init_apic_ldr();
1564
1565 /*
1566 * Set Task Priority to 'accept all except vectors 0-31'. An APIC
1567 * vector in the 16-31 range could be delivered if TPR == 0, but we
1568 * would think it's an exception and terrible things will happen. We
1569 * never change this later on.
1570 */
1571 value = apic_read(APIC_TASKPRI);
1572 value &= ~APIC_TPRI_MASK;
1573 value |= 0x10;
1574 apic_write(APIC_TASKPRI, value);
1575
1576 /* Clear eventually stale ISR/IRR bits */
1577 apic_pending_intr_clear();
1578
1579 /*
1580 * Now that we are all set up, enable the APIC
1581 */
1582 value = apic_read(APIC_SPIV);
1583 value &= ~APIC_VECTOR_MASK;
1584 /*
1585 * Enable APIC
1586 */
1587 value |= APIC_SPIV_APIC_ENABLED;
1588
1589#ifdef CONFIG_X86_32
1590 /*
1591 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1592 * certain networking cards. If high frequency interrupts are
1593 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1594 * entry is masked/unmasked at a high rate as well then sooner or
1595 * later IOAPIC line gets 'stuck', no more interrupts are received
1596 * from the device. If focus CPU is disabled then the hang goes
1597 * away, oh well :-(
1598 *
1599 * [ This bug can be reproduced easily with a level-triggered
1600 * PCI Ne2000 networking cards and PII/PIII processors, dual
1601 * BX chipset. ]
1602 */
1603 /*
1604 * Actually disabling the focus CPU check just makes the hang less
1605 * frequent as it makes the interrupt distribution model be more
1606 * like LRU than MRU (the short-term load is more even across CPUs).
1607 */
1608
1609 /*
1610 * - enable focus processor (bit==0)
1611 * - 64bit mode always use processor focus
1612 * so no need to set it
1613 */
1614 value &= ~APIC_SPIV_FOCUS_DISABLED;
1615#endif
1616
1617 /*
1618 * Set spurious IRQ vector
1619 */
1620 value |= SPURIOUS_APIC_VECTOR;
1621 apic_write(APIC_SPIV, value);
1622
1623 perf_events_lapic_init();
1624
1625 /*
1626 * Set up LVT0, LVT1:
1627 *
1628 * set up through-local-APIC on the boot CPU's LINT0. This is not
1629 * strictly necessary in pure symmetric-IO mode, but sometimes
1630 * we delegate interrupts to the 8259A.
1631 */
1632 /*
1633 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1634 */
1635 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1636 if (!cpu && (pic_mode || !value || ioapic_is_disabled)) {
1637 value = APIC_DM_EXTINT;
1638 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n", cpu);
1639 } else {
1640 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1641 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n", cpu);
1642 }
1643 apic_write(APIC_LVT0, value);
1644
1645 /*
1646 * Only the BSP sees the LINT1 NMI signal by default. This can be
1647 * modified by apic_extnmi= boot option.
1648 */
1649 if ((!cpu && apic_extnmi != APIC_EXTNMI_NONE) ||
1650 apic_extnmi == APIC_EXTNMI_ALL)
1651 value = APIC_DM_NMI;
1652 else
1653 value = APIC_DM_NMI | APIC_LVT_MASKED;
1654
1655 /* Is 82489DX ? */
1656 if (!lapic_is_integrated())
1657 value |= APIC_LVT_LEVEL_TRIGGER;
1658 apic_write(APIC_LVT1, value);
1659
1660#ifdef CONFIG_X86_MCE_INTEL
1661 /* Recheck CMCI information after local APIC is up on CPU #0 */
1662 if (!cpu)
1663 cmci_recheck();
1664#endif
1665}
1666
1667static void end_local_APIC_setup(void)
1668{
1669 lapic_setup_esr();
1670
1671#ifdef CONFIG_X86_32
1672 {
1673 unsigned int value;
1674 /* Disable the local apic timer */
1675 value = apic_read(APIC_LVTT);
1676 value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1677 apic_write(APIC_LVTT, value);
1678 }
1679#endif
1680
1681 apic_pm_activate();
1682}
1683
1684/*
1685 * APIC setup function for application processors. Called from smpboot.c
1686 */
1687void apic_ap_setup(void)
1688{
1689 setup_local_APIC();
1690 end_local_APIC_setup();
1691}
1692
1693static __init void cpu_set_boot_apic(void);
1694
1695static __init void apic_read_boot_cpu_id(bool x2apic)
1696{
1697 /*
1698 * This can be invoked from check_x2apic() before the APIC has been
1699 * selected. But that code knows for sure that the BIOS enabled
1700 * X2APIC.
1701 */
1702 if (x2apic) {
1703 boot_cpu_physical_apicid = native_apic_msr_read(APIC_ID);
1704 boot_cpu_apic_version = GET_APIC_VERSION(native_apic_msr_read(APIC_LVR));
1705 } else {
1706 boot_cpu_physical_apicid = read_apic_id();
1707 boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
1708 }
1709 cpu_set_boot_apic();
1710}
1711
1712#ifdef CONFIG_X86_X2APIC
1713int x2apic_mode;
1714EXPORT_SYMBOL_GPL(x2apic_mode);
1715
1716enum {
1717 X2APIC_OFF,
1718 X2APIC_DISABLED,
1719 /* All states below here have X2APIC enabled */
1720 X2APIC_ON,
1721 X2APIC_ON_LOCKED
1722};
1723static int x2apic_state;
1724
1725static bool x2apic_hw_locked(void)
1726{
1727 u64 ia32_cap;
1728 u64 msr;
1729
1730 ia32_cap = x86_read_arch_cap_msr();
1731 if (ia32_cap & ARCH_CAP_XAPIC_DISABLE) {
1732 rdmsrl(MSR_IA32_XAPIC_DISABLE_STATUS, msr);
1733 return (msr & LEGACY_XAPIC_DISABLED);
1734 }
1735 return false;
1736}
1737
1738static void __x2apic_disable(void)
1739{
1740 u64 msr;
1741
1742 if (!boot_cpu_has(X86_FEATURE_APIC))
1743 return;
1744
1745 rdmsrl(MSR_IA32_APICBASE, msr);
1746 if (!(msr & X2APIC_ENABLE))
1747 return;
1748 /* Disable xapic and x2apic first and then reenable xapic mode */
1749 wrmsrl(MSR_IA32_APICBASE, msr & ~(X2APIC_ENABLE | XAPIC_ENABLE));
1750 wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE);
1751 printk_once(KERN_INFO "x2apic disabled\n");
1752}
1753
1754static void __x2apic_enable(void)
1755{
1756 u64 msr;
1757
1758 rdmsrl(MSR_IA32_APICBASE, msr);
1759 if (msr & X2APIC_ENABLE)
1760 return;
1761 wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE);
1762 printk_once(KERN_INFO "x2apic enabled\n");
1763}
1764
1765static int __init setup_nox2apic(char *str)
1766{
1767 if (x2apic_enabled()) {
1768 u32 apicid = native_apic_msr_read(APIC_ID);
1769
1770 if (apicid >= 255) {
1771 pr_warn("Apicid: %08x, cannot enforce nox2apic\n",
1772 apicid);
1773 return 0;
1774 }
1775 if (x2apic_hw_locked()) {
1776 pr_warn("APIC locked in x2apic mode, can't disable\n");
1777 return 0;
1778 }
1779 pr_warn("x2apic already enabled.\n");
1780 __x2apic_disable();
1781 }
1782 setup_clear_cpu_cap(X86_FEATURE_X2APIC);
1783 x2apic_state = X2APIC_DISABLED;
1784 x2apic_mode = 0;
1785 return 0;
1786}
1787early_param("nox2apic", setup_nox2apic);
1788
1789/* Called from cpu_init() to enable x2apic on (secondary) cpus */
1790void x2apic_setup(void)
1791{
1792 /*
1793 * Try to make the AP's APIC state match that of the BSP, but if the
1794 * BSP is unlocked and the AP is locked then there is a state mismatch.
1795 * Warn about the mismatch in case a GP fault occurs due to a locked AP
1796 * trying to be turned off.
1797 */
1798 if (x2apic_state != X2APIC_ON_LOCKED && x2apic_hw_locked())
1799 pr_warn("x2apic lock mismatch between BSP and AP.\n");
1800 /*
1801 * If x2apic is not in ON or LOCKED state, disable it if already enabled
1802 * from BIOS.
1803 */
1804 if (x2apic_state < X2APIC_ON) {
1805 __x2apic_disable();
1806 return;
1807 }
1808 __x2apic_enable();
1809}
1810
1811static __init void apic_set_fixmap(void);
1812
1813static __init void x2apic_disable(void)
1814{
1815 u32 x2apic_id, state = x2apic_state;
1816
1817 x2apic_mode = 0;
1818 x2apic_state = X2APIC_DISABLED;
1819
1820 if (state != X2APIC_ON)
1821 return;
1822
1823 x2apic_id = read_apic_id();
1824 if (x2apic_id >= 255)
1825 panic("Cannot disable x2apic, id: %08x\n", x2apic_id);
1826
1827 if (x2apic_hw_locked()) {
1828 pr_warn("Cannot disable locked x2apic, id: %08x\n", x2apic_id);
1829 return;
1830 }
1831
1832 __x2apic_disable();
1833 apic_set_fixmap();
1834}
1835
1836static __init void x2apic_enable(void)
1837{
1838 if (x2apic_state != X2APIC_OFF)
1839 return;
1840
1841 x2apic_mode = 1;
1842 x2apic_state = X2APIC_ON;
1843 __x2apic_enable();
1844}
1845
1846static __init void try_to_enable_x2apic(int remap_mode)
1847{
1848 if (x2apic_state == X2APIC_DISABLED)
1849 return;
1850
1851 if (remap_mode != IRQ_REMAP_X2APIC_MODE) {
1852 u32 apic_limit = 255;
1853
1854 /*
1855 * Using X2APIC without IR is not architecturally supported
1856 * on bare metal but may be supported in guests.
1857 */
1858 if (!x86_init.hyper.x2apic_available()) {
1859 pr_info("x2apic: IRQ remapping doesn't support X2APIC mode\n");
1860 x2apic_disable();
1861 return;
1862 }
1863
1864 /*
1865 * If the hypervisor supports extended destination ID in
1866 * MSI, that increases the maximum APIC ID that can be
1867 * used for non-remapped IRQ domains.
1868 */
1869 if (x86_init.hyper.msi_ext_dest_id()) {
1870 virt_ext_dest_id = 1;
1871 apic_limit = 32767;
1872 }
1873
1874 /*
1875 * Without IR, all CPUs can be addressed by IOAPIC/MSI only
1876 * in physical mode, and CPUs with an APIC ID that cannot
1877 * be addressed must not be brought online.
1878 */
1879 x2apic_set_max_apicid(apic_limit);
1880 x2apic_phys = 1;
1881 }
1882 x2apic_enable();
1883}
1884
1885void __init check_x2apic(void)
1886{
1887 if (x2apic_enabled()) {
1888 pr_info("x2apic: enabled by BIOS, switching to x2apic ops\n");
1889 x2apic_mode = 1;
1890 if (x2apic_hw_locked())
1891 x2apic_state = X2APIC_ON_LOCKED;
1892 else
1893 x2apic_state = X2APIC_ON;
1894 apic_read_boot_cpu_id(true);
1895 } else if (!boot_cpu_has(X86_FEATURE_X2APIC)) {
1896 x2apic_state = X2APIC_DISABLED;
1897 }
1898}
1899#else /* CONFIG_X86_X2APIC */
1900void __init check_x2apic(void)
1901{
1902 if (!apic_is_x2apic_enabled())
1903 return;
1904 /*
1905 * Checkme: Can we simply turn off x2APIC here instead of disabling the APIC?
1906 */
1907 pr_err("Kernel does not support x2APIC, please recompile with CONFIG_X86_X2APIC.\n");
1908 pr_err("Disabling APIC, expect reduced performance and functionality.\n");
1909
1910 apic_is_disabled = true;
1911 setup_clear_cpu_cap(X86_FEATURE_APIC);
1912}
1913
1914static inline void try_to_enable_x2apic(int remap_mode) { }
1915static inline void __x2apic_enable(void) { }
1916#endif /* !CONFIG_X86_X2APIC */
1917
1918void __init enable_IR_x2apic(void)
1919{
1920 unsigned long flags;
1921 int ret, ir_stat;
1922
1923 if (ioapic_is_disabled) {
1924 pr_info("Not enabling interrupt remapping due to skipped IO-APIC setup\n");
1925 return;
1926 }
1927
1928 ir_stat = irq_remapping_prepare();
1929 if (ir_stat < 0 && !x2apic_supported())
1930 return;
1931
1932 ret = save_ioapic_entries();
1933 if (ret) {
1934 pr_info("Saving IO-APIC state failed: %d\n", ret);
1935 return;
1936 }
1937
1938 local_irq_save(flags);
1939 legacy_pic->mask_all();
1940 mask_ioapic_entries();
1941
1942 /* If irq_remapping_prepare() succeeded, try to enable it */
1943 if (ir_stat >= 0)
1944 ir_stat = irq_remapping_enable();
1945 /* ir_stat contains the remap mode or an error code */
1946 try_to_enable_x2apic(ir_stat);
1947
1948 if (ir_stat < 0)
1949 restore_ioapic_entries();
1950 legacy_pic->restore_mask();
1951 local_irq_restore(flags);
1952}
1953
1954#ifdef CONFIG_X86_64
1955/*
1956 * Detect and enable local APICs on non-SMP boards.
1957 * Original code written by Keir Fraser.
1958 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1959 * not correctly set up (usually the APIC timer won't work etc.)
1960 */
1961static bool __init detect_init_APIC(void)
1962{
1963 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1964 pr_info("No local APIC present\n");
1965 return false;
1966 }
1967
1968 register_lapic_address(APIC_DEFAULT_PHYS_BASE);
1969 return true;
1970}
1971#else
1972
1973static bool __init apic_verify(unsigned long addr)
1974{
1975 u32 features, h, l;
1976
1977 /*
1978 * The APIC feature bit should now be enabled
1979 * in `cpuid'
1980 */
1981 features = cpuid_edx(1);
1982 if (!(features & (1 << X86_FEATURE_APIC))) {
1983 pr_warn("Could not enable APIC!\n");
1984 return false;
1985 }
1986 set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1987
1988 /* The BIOS may have set up the APIC at some other address */
1989 if (boot_cpu_data.x86 >= 6) {
1990 rdmsr(MSR_IA32_APICBASE, l, h);
1991 if (l & MSR_IA32_APICBASE_ENABLE)
1992 addr = l & MSR_IA32_APICBASE_BASE;
1993 }
1994
1995 register_lapic_address(addr);
1996 pr_info("Found and enabled local APIC!\n");
1997 return true;
1998}
1999
2000bool __init apic_force_enable(unsigned long addr)
2001{
2002 u32 h, l;
2003
2004 if (apic_is_disabled)
2005 return false;
2006
2007 /*
2008 * Some BIOSes disable the local APIC in the APIC_BASE
2009 * MSR. This can only be done in software for Intel P6 or later
2010 * and AMD K7 (Model > 1) or later.
2011 */
2012 if (boot_cpu_data.x86 >= 6) {
2013 rdmsr(MSR_IA32_APICBASE, l, h);
2014 if (!(l & MSR_IA32_APICBASE_ENABLE)) {
2015 pr_info("Local APIC disabled by BIOS -- reenabling.\n");
2016 l &= ~MSR_IA32_APICBASE_BASE;
2017 l |= MSR_IA32_APICBASE_ENABLE | addr;
2018 wrmsr(MSR_IA32_APICBASE, l, h);
2019 enabled_via_apicbase = 1;
2020 }
2021 }
2022 return apic_verify(addr);
2023}
2024
2025/*
2026 * Detect and initialize APIC
2027 */
2028static bool __init detect_init_APIC(void)
2029{
2030 /* Disabled by kernel option? */
2031 if (apic_is_disabled)
2032 return false;
2033
2034 switch (boot_cpu_data.x86_vendor) {
2035 case X86_VENDOR_AMD:
2036 if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
2037 (boot_cpu_data.x86 >= 15))
2038 break;
2039 goto no_apic;
2040 case X86_VENDOR_HYGON:
2041 break;
2042 case X86_VENDOR_INTEL:
2043 if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
2044 (boot_cpu_data.x86 == 5 && boot_cpu_has(X86_FEATURE_APIC)))
2045 break;
2046 goto no_apic;
2047 default:
2048 goto no_apic;
2049 }
2050
2051 if (!boot_cpu_has(X86_FEATURE_APIC)) {
2052 /*
2053 * Over-ride BIOS and try to enable the local APIC only if
2054 * "lapic" specified.
2055 */
2056 if (!force_enable_local_apic) {
2057 pr_info("Local APIC disabled by BIOS -- "
2058 "you can enable it with \"lapic\"\n");
2059 return false;
2060 }
2061 if (!apic_force_enable(APIC_DEFAULT_PHYS_BASE))
2062 return false;
2063 } else {
2064 if (!apic_verify(APIC_DEFAULT_PHYS_BASE))
2065 return false;
2066 }
2067
2068 apic_pm_activate();
2069
2070 return true;
2071
2072no_apic:
2073 pr_info("No local APIC present or hardware disabled\n");
2074 return false;
2075}
2076#endif
2077
2078/**
2079 * init_apic_mappings - initialize APIC mappings
2080 */
2081void __init init_apic_mappings(void)
2082{
2083 if (apic_validate_deadline_timer())
2084 pr_info("TSC deadline timer available\n");
2085
2086 if (x2apic_mode)
2087 return;
2088
2089 if (!smp_found_config) {
2090 if (!detect_init_APIC()) {
2091 pr_info("APIC: disable apic facility\n");
2092 apic_disable();
2093 }
2094 num_processors = 1;
2095 }
2096}
2097
2098static __init void apic_set_fixmap(void)
2099{
2100 set_fixmap_nocache(FIX_APIC_BASE, mp_lapic_addr);
2101 apic_mmio_base = APIC_BASE;
2102 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
2103 apic_mmio_base, mp_lapic_addr);
2104 apic_read_boot_cpu_id(false);
2105}
2106
2107void __init register_lapic_address(unsigned long address)
2108{
2109 /* This should only happen once */
2110 WARN_ON_ONCE(mp_lapic_addr);
2111 mp_lapic_addr = address;
2112
2113 if (!x2apic_mode)
2114 apic_set_fixmap();
2115}
2116
2117/*
2118 * Local APIC interrupts
2119 */
2120
2121/*
2122 * Common handling code for spurious_interrupt and spurious_vector entry
2123 * points below. No point in allowing the compiler to inline it twice.
2124 */
2125static noinline void handle_spurious_interrupt(u8 vector)
2126{
2127 u32 v;
2128
2129 trace_spurious_apic_entry(vector);
2130
2131 inc_irq_stat(irq_spurious_count);
2132
2133 /*
2134 * If this is a spurious interrupt then do not acknowledge
2135 */
2136 if (vector == SPURIOUS_APIC_VECTOR) {
2137 /* See SDM vol 3 */
2138 pr_info("Spurious APIC interrupt (vector 0xFF) on CPU#%d, should never happen.\n",
2139 smp_processor_id());
2140 goto out;
2141 }
2142
2143 /*
2144 * If it is a vectored one, verify it's set in the ISR. If set,
2145 * acknowledge it.
2146 */
2147 v = apic_read(APIC_ISR + ((vector & ~0x1f) >> 1));
2148 if (v & (1 << (vector & 0x1f))) {
2149 pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Acked\n",
2150 vector, smp_processor_id());
2151 apic_eoi();
2152 } else {
2153 pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Not pending!\n",
2154 vector, smp_processor_id());
2155 }
2156out:
2157 trace_spurious_apic_exit(vector);
2158}
2159
2160/**
2161 * spurious_interrupt - Catch all for interrupts raised on unused vectors
2162 * @regs: Pointer to pt_regs on stack
2163 * @vector: The vector number
2164 *
2165 * This is invoked from ASM entry code to catch all interrupts which
2166 * trigger on an entry which is routed to the common_spurious idtentry
2167 * point.
2168 */
2169DEFINE_IDTENTRY_IRQ(spurious_interrupt)
2170{
2171 handle_spurious_interrupt(vector);
2172}
2173
2174DEFINE_IDTENTRY_SYSVEC(sysvec_spurious_apic_interrupt)
2175{
2176 handle_spurious_interrupt(SPURIOUS_APIC_VECTOR);
2177}
2178
2179/*
2180 * This interrupt should never happen with our APIC/SMP architecture
2181 */
2182DEFINE_IDTENTRY_SYSVEC(sysvec_error_interrupt)
2183{
2184 static const char * const error_interrupt_reason[] = {
2185 "Send CS error", /* APIC Error Bit 0 */
2186 "Receive CS error", /* APIC Error Bit 1 */
2187 "Send accept error", /* APIC Error Bit 2 */
2188 "Receive accept error", /* APIC Error Bit 3 */
2189 "Redirectable IPI", /* APIC Error Bit 4 */
2190 "Send illegal vector", /* APIC Error Bit 5 */
2191 "Received illegal vector", /* APIC Error Bit 6 */
2192 "Illegal register address", /* APIC Error Bit 7 */
2193 };
2194 u32 v, i = 0;
2195
2196 trace_error_apic_entry(ERROR_APIC_VECTOR);
2197
2198 /* First tickle the hardware, only then report what went on. -- REW */
2199 if (lapic_get_maxlvt() > 3) /* Due to the Pentium erratum 3AP. */
2200 apic_write(APIC_ESR, 0);
2201 v = apic_read(APIC_ESR);
2202 apic_eoi();
2203 atomic_inc(&irq_err_count);
2204
2205 apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x",
2206 smp_processor_id(), v);
2207
2208 v &= 0xff;
2209 while (v) {
2210 if (v & 0x1)
2211 apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]);
2212 i++;
2213 v >>= 1;
2214 }
2215
2216 apic_printk(APIC_DEBUG, KERN_CONT "\n");
2217
2218 trace_error_apic_exit(ERROR_APIC_VECTOR);
2219}
2220
2221/**
2222 * connect_bsp_APIC - attach the APIC to the interrupt system
2223 */
2224static void __init connect_bsp_APIC(void)
2225{
2226#ifdef CONFIG_X86_32
2227 if (pic_mode) {
2228 /*
2229 * Do not trust the local APIC being empty at bootup.
2230 */
2231 clear_local_APIC();
2232 /*
2233 * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
2234 * local APIC to INT and NMI lines.
2235 */
2236 apic_printk(APIC_VERBOSE, "leaving PIC mode, "
2237 "enabling APIC mode.\n");
2238 imcr_pic_to_apic();
2239 }
2240#endif
2241}
2242
2243/**
2244 * disconnect_bsp_APIC - detach the APIC from the interrupt system
2245 * @virt_wire_setup: indicates, whether virtual wire mode is selected
2246 *
2247 * Virtual wire mode is necessary to deliver legacy interrupts even when the
2248 * APIC is disabled.
2249 */
2250void disconnect_bsp_APIC(int virt_wire_setup)
2251{
2252 unsigned int value;
2253
2254#ifdef CONFIG_X86_32
2255 if (pic_mode) {
2256 /*
2257 * Put the board back into PIC mode (has an effect only on
2258 * certain older boards). Note that APIC interrupts, including
2259 * IPIs, won't work beyond this point! The only exception are
2260 * INIT IPIs.
2261 */
2262 apic_printk(APIC_VERBOSE, "disabling APIC mode, "
2263 "entering PIC mode.\n");
2264 imcr_apic_to_pic();
2265 return;
2266 }
2267#endif
2268
2269 /* Go back to Virtual Wire compatibility mode */
2270
2271 /* For the spurious interrupt use vector F, and enable it */
2272 value = apic_read(APIC_SPIV);
2273 value &= ~APIC_VECTOR_MASK;
2274 value |= APIC_SPIV_APIC_ENABLED;
2275 value |= 0xf;
2276 apic_write(APIC_SPIV, value);
2277
2278 if (!virt_wire_setup) {
2279 /*
2280 * For LVT0 make it edge triggered, active high,
2281 * external and enabled
2282 */
2283 value = apic_read(APIC_LVT0);
2284 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2285 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2286 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2287 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2288 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
2289 apic_write(APIC_LVT0, value);
2290 } else {
2291 /* Disable LVT0 */
2292 apic_write(APIC_LVT0, APIC_LVT_MASKED);
2293 }
2294
2295 /*
2296 * For LVT1 make it edge triggered, active high,
2297 * nmi and enabled
2298 */
2299 value = apic_read(APIC_LVT1);
2300 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2301 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2302 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2303 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2304 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
2305 apic_write(APIC_LVT1, value);
2306}
2307
2308/*
2309 * The number of allocated logical CPU IDs. Since logical CPU IDs are allocated
2310 * contiguously, it equals to current allocated max logical CPU ID plus 1.
2311 * All allocated CPU IDs should be in the [0, nr_logical_cpuids) range,
2312 * so the maximum of nr_logical_cpuids is nr_cpu_ids.
2313 *
2314 * NOTE: Reserve 0 for BSP.
2315 */
2316static int nr_logical_cpuids = 1;
2317
2318/*
2319 * Used to store mapping between logical CPU IDs and APIC IDs.
2320 */
2321u32 cpuid_to_apicid[] = { [0 ... NR_CPUS - 1] = BAD_APICID, };
2322
2323bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
2324{
2325 return phys_id == (u64)cpuid_to_apicid[cpu];
2326}
2327
2328#ifdef CONFIG_SMP
2329static void cpu_mark_primary_thread(unsigned int cpu, unsigned int apicid)
2330{
2331 /* Isolate the SMT bit(s) in the APICID and check for 0 */
2332 u32 mask = (1U << (fls(smp_num_siblings) - 1)) - 1;
2333
2334 if (smp_num_siblings == 1 || !(apicid & mask))
2335 cpumask_set_cpu(cpu, &__cpu_primary_thread_mask);
2336}
2337
2338/*
2339 * Due to the utter mess of CPUID evaluation smp_num_siblings is not valid
2340 * during early boot. Initialize the primary thread mask before SMP
2341 * bringup.
2342 */
2343static int __init smp_init_primary_thread_mask(void)
2344{
2345 unsigned int cpu;
2346
2347 /*
2348 * XEN/PV provides either none or useless topology information.
2349 * Pretend that all vCPUs are primary threads.
2350 */
2351 if (xen_pv_domain()) {
2352 cpumask_copy(&__cpu_primary_thread_mask, cpu_possible_mask);
2353 return 0;
2354 }
2355
2356 for (cpu = 0; cpu < nr_logical_cpuids; cpu++)
2357 cpu_mark_primary_thread(cpu, cpuid_to_apicid[cpu]);
2358 return 0;
2359}
2360early_initcall(smp_init_primary_thread_mask);
2361#else
2362static inline void cpu_mark_primary_thread(unsigned int cpu, unsigned int apicid) { }
2363#endif
2364
2365/*
2366 * Should use this API to allocate logical CPU IDs to keep nr_logical_cpuids
2367 * and cpuid_to_apicid[] synchronized.
2368 */
2369static int allocate_logical_cpuid(int apicid)
2370{
2371 int i;
2372
2373 /*
2374 * cpuid <-> apicid mapping is persistent, so when a cpu is up,
2375 * check if the kernel has allocated a cpuid for it.
2376 */
2377 for (i = 0; i < nr_logical_cpuids; i++) {
2378 if (cpuid_to_apicid[i] == apicid)
2379 return i;
2380 }
2381
2382 /* Allocate a new cpuid. */
2383 if (nr_logical_cpuids >= nr_cpu_ids) {
2384 WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %u reached. "
2385 "Processor %d/0x%x and the rest are ignored.\n",
2386 nr_cpu_ids, nr_logical_cpuids, apicid);
2387 return -EINVAL;
2388 }
2389
2390 cpuid_to_apicid[nr_logical_cpuids] = apicid;
2391 return nr_logical_cpuids++;
2392}
2393
2394static void cpu_update_apic(int cpu, u32 apicid)
2395{
2396#if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
2397 early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
2398#endif
2399 set_cpu_possible(cpu, true);
2400 physid_set(apicid, phys_cpu_present_map);
2401 set_cpu_present(cpu, true);
2402 num_processors++;
2403
2404 if (system_state != SYSTEM_BOOTING)
2405 cpu_mark_primary_thread(cpu, apicid);
2406}
2407
2408static __init void cpu_set_boot_apic(void)
2409{
2410 cpuid_to_apicid[0] = boot_cpu_physical_apicid;
2411 cpu_update_apic(0, boot_cpu_physical_apicid);
2412 x86_32_probe_bigsmp_early();
2413}
2414
2415int generic_processor_info(int apicid)
2416{
2417 int cpu, max = nr_cpu_ids;
2418
2419 /* The boot CPU must be set before MADT/MPTABLE parsing happens */
2420 if (cpuid_to_apicid[0] == BAD_APICID)
2421 panic("Boot CPU APIC not registered yet\n");
2422
2423 if (apicid == boot_cpu_physical_apicid)
2424 return 0;
2425
2426 if (disabled_cpu_apicid == apicid) {
2427 int thiscpu = num_processors + disabled_cpus;
2428
2429 pr_warn("APIC: Disabling requested cpu. Processor %d/0x%x ignored.\n",
2430 thiscpu, apicid);
2431
2432 disabled_cpus++;
2433 return -ENODEV;
2434 }
2435
2436 if (num_processors >= nr_cpu_ids) {
2437 int thiscpu = max + disabled_cpus;
2438
2439 pr_warn("APIC: NR_CPUS/possible_cpus limit of %i reached. "
2440 "Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
2441
2442 disabled_cpus++;
2443 return -EINVAL;
2444 }
2445
2446 cpu = allocate_logical_cpuid(apicid);
2447 if (cpu < 0) {
2448 disabled_cpus++;
2449 return -EINVAL;
2450 }
2451
2452 cpu_update_apic(cpu, apicid);
2453 return cpu;
2454}
2455
2456
2457void __irq_msi_compose_msg(struct irq_cfg *cfg, struct msi_msg *msg,
2458 bool dmar)
2459{
2460 memset(msg, 0, sizeof(*msg));
2461
2462 msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW;
2463 msg->arch_addr_lo.dest_mode_logical = apic->dest_mode_logical;
2464 msg->arch_addr_lo.destid_0_7 = cfg->dest_apicid & 0xFF;
2465
2466 msg->arch_data.delivery_mode = APIC_DELIVERY_MODE_FIXED;
2467 msg->arch_data.vector = cfg->vector;
2468
2469 msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
2470 /*
2471 * Only the IOMMU itself can use the trick of putting destination
2472 * APIC ID into the high bits of the address. Anything else would
2473 * just be writing to memory if it tried that, and needs IR to
2474 * address APICs which can't be addressed in the normal 32-bit
2475 * address range at 0xFFExxxxx. That is typically just 8 bits, but
2476 * some hypervisors allow the extended destination ID field in bits
2477 * 5-11 to be used, giving support for 15 bits of APIC IDs in total.
2478 */
2479 if (dmar)
2480 msg->arch_addr_hi.destid_8_31 = cfg->dest_apicid >> 8;
2481 else if (virt_ext_dest_id && cfg->dest_apicid < 0x8000)
2482 msg->arch_addr_lo.virt_destid_8_14 = cfg->dest_apicid >> 8;
2483 else
2484 WARN_ON_ONCE(cfg->dest_apicid > 0xFF);
2485}
2486
2487u32 x86_msi_msg_get_destid(struct msi_msg *msg, bool extid)
2488{
2489 u32 dest = msg->arch_addr_lo.destid_0_7;
2490
2491 if (extid)
2492 dest |= msg->arch_addr_hi.destid_8_31 << 8;
2493 return dest;
2494}
2495EXPORT_SYMBOL_GPL(x86_msi_msg_get_destid);
2496
2497static void __init apic_bsp_up_setup(void)
2498{
2499#ifdef CONFIG_X86_64
2500 apic_write(APIC_ID, apic->set_apic_id(boot_cpu_physical_apicid));
2501#endif
2502 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
2503}
2504
2505/**
2506 * apic_bsp_setup - Setup function for local apic and io-apic
2507 * @upmode: Force UP mode (for APIC_init_uniprocessor)
2508 */
2509static void __init apic_bsp_setup(bool upmode)
2510{
2511 connect_bsp_APIC();
2512 if (upmode)
2513 apic_bsp_up_setup();
2514 setup_local_APIC();
2515
2516 enable_IO_APIC();
2517 end_local_APIC_setup();
2518 irq_remap_enable_fault_handling();
2519 setup_IO_APIC();
2520 lapic_update_legacy_vectors();
2521}
2522
2523#ifdef CONFIG_UP_LATE_INIT
2524void __init up_late_init(void)
2525{
2526 if (apic_intr_mode == APIC_PIC)
2527 return;
2528
2529 /* Setup local timer */
2530 x86_init.timers.setup_percpu_clockev();
2531}
2532#endif
2533
2534/*
2535 * Power management
2536 */
2537#ifdef CONFIG_PM
2538
2539static struct {
2540 /*
2541 * 'active' is true if the local APIC was enabled by us and
2542 * not the BIOS; this signifies that we are also responsible
2543 * for disabling it before entering apm/acpi suspend
2544 */
2545 int active;
2546 /* r/w apic fields */
2547 u32 apic_id;
2548 unsigned int apic_taskpri;
2549 unsigned int apic_ldr;
2550 unsigned int apic_dfr;
2551 unsigned int apic_spiv;
2552 unsigned int apic_lvtt;
2553 unsigned int apic_lvtpc;
2554 unsigned int apic_lvt0;
2555 unsigned int apic_lvt1;
2556 unsigned int apic_lvterr;
2557 unsigned int apic_tmict;
2558 unsigned int apic_tdcr;
2559 unsigned int apic_thmr;
2560 unsigned int apic_cmci;
2561} apic_pm_state;
2562
2563static int lapic_suspend(void)
2564{
2565 unsigned long flags;
2566 int maxlvt;
2567
2568 if (!apic_pm_state.active)
2569 return 0;
2570
2571 maxlvt = lapic_get_maxlvt();
2572
2573 apic_pm_state.apic_id = apic_read(APIC_ID);
2574 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
2575 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
2576 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
2577 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
2578 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
2579 if (maxlvt >= 4)
2580 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
2581 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
2582 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
2583 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
2584 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
2585 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
2586#ifdef CONFIG_X86_THERMAL_VECTOR
2587 if (maxlvt >= 5)
2588 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
2589#endif
2590#ifdef CONFIG_X86_MCE_INTEL
2591 if (maxlvt >= 6)
2592 apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
2593#endif
2594
2595 local_irq_save(flags);
2596
2597 /*
2598 * Mask IOAPIC before disabling the local APIC to prevent stale IRR
2599 * entries on some implementations.
2600 */
2601 mask_ioapic_entries();
2602
2603 disable_local_APIC();
2604
2605 irq_remapping_disable();
2606
2607 local_irq_restore(flags);
2608 return 0;
2609}
2610
2611static void lapic_resume(void)
2612{
2613 unsigned int l, h;
2614 unsigned long flags;
2615 int maxlvt;
2616
2617 if (!apic_pm_state.active)
2618 return;
2619
2620 local_irq_save(flags);
2621
2622 /*
2623 * IO-APIC and PIC have their own resume routines.
2624 * We just mask them here to make sure the interrupt
2625 * subsystem is completely quiet while we enable x2apic
2626 * and interrupt-remapping.
2627 */
2628 mask_ioapic_entries();
2629 legacy_pic->mask_all();
2630
2631 if (x2apic_mode) {
2632 __x2apic_enable();
2633 } else {
2634 /*
2635 * Make sure the APICBASE points to the right address
2636 *
2637 * FIXME! This will be wrong if we ever support suspend on
2638 * SMP! We'll need to do this as part of the CPU restore!
2639 */
2640 if (boot_cpu_data.x86 >= 6) {
2641 rdmsr(MSR_IA32_APICBASE, l, h);
2642 l &= ~MSR_IA32_APICBASE_BASE;
2643 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
2644 wrmsr(MSR_IA32_APICBASE, l, h);
2645 }
2646 }
2647
2648 maxlvt = lapic_get_maxlvt();
2649 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
2650 apic_write(APIC_ID, apic_pm_state.apic_id);
2651 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2652 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2653 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2654 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2655 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2656 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2657#ifdef CONFIG_X86_THERMAL_VECTOR
2658 if (maxlvt >= 5)
2659 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2660#endif
2661#ifdef CONFIG_X86_MCE_INTEL
2662 if (maxlvt >= 6)
2663 apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
2664#endif
2665 if (maxlvt >= 4)
2666 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2667 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2668 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2669 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2670 apic_write(APIC_ESR, 0);
2671 apic_read(APIC_ESR);
2672 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2673 apic_write(APIC_ESR, 0);
2674 apic_read(APIC_ESR);
2675
2676 irq_remapping_reenable(x2apic_mode);
2677
2678 local_irq_restore(flags);
2679}
2680
2681/*
2682 * This device has no shutdown method - fully functioning local APICs
2683 * are needed on every CPU up until machine_halt/restart/poweroff.
2684 */
2685
2686static struct syscore_ops lapic_syscore_ops = {
2687 .resume = lapic_resume,
2688 .suspend = lapic_suspend,
2689};
2690
2691static void apic_pm_activate(void)
2692{
2693 apic_pm_state.active = 1;
2694}
2695
2696static int __init init_lapic_sysfs(void)
2697{
2698 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2699 if (boot_cpu_has(X86_FEATURE_APIC))
2700 register_syscore_ops(&lapic_syscore_ops);
2701
2702 return 0;
2703}
2704
2705/* local apic needs to resume before other devices access its registers. */
2706core_initcall(init_lapic_sysfs);
2707
2708#else /* CONFIG_PM */
2709
2710static void apic_pm_activate(void) { }
2711
2712#endif /* CONFIG_PM */
2713
2714#ifdef CONFIG_X86_64
2715
2716static int multi_checked;
2717static int multi;
2718
2719static int set_multi(const struct dmi_system_id *d)
2720{
2721 if (multi)
2722 return 0;
2723 pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
2724 multi = 1;
2725 return 0;
2726}
2727
2728static const struct dmi_system_id multi_dmi_table[] = {
2729 {
2730 .callback = set_multi,
2731 .ident = "IBM System Summit2",
2732 .matches = {
2733 DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2734 DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
2735 },
2736 },
2737 {}
2738};
2739
2740static void dmi_check_multi(void)
2741{
2742 if (multi_checked)
2743 return;
2744
2745 dmi_check_system(multi_dmi_table);
2746 multi_checked = 1;
2747}
2748
2749/*
2750 * apic_is_clustered_box() -- Check if we can expect good TSC
2751 *
2752 * Thus far, the major user of this is IBM's Summit2 series:
2753 * Clustered boxes may have unsynced TSC problems if they are
2754 * multi-chassis.
2755 * Use DMI to check them
2756 */
2757int apic_is_clustered_box(void)
2758{
2759 dmi_check_multi();
2760 return multi;
2761}
2762#endif
2763
2764/*
2765 * APIC command line parameters
2766 */
2767static int __init setup_disableapic(char *arg)
2768{
2769 apic_is_disabled = true;
2770 setup_clear_cpu_cap(X86_FEATURE_APIC);
2771 return 0;
2772}
2773early_param("disableapic", setup_disableapic);
2774
2775/* same as disableapic, for compatibility */
2776static int __init setup_nolapic(char *arg)
2777{
2778 return setup_disableapic(arg);
2779}
2780early_param("nolapic", setup_nolapic);
2781
2782static int __init parse_lapic_timer_c2_ok(char *arg)
2783{
2784 local_apic_timer_c2_ok = 1;
2785 return 0;
2786}
2787early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2788
2789static int __init parse_disable_apic_timer(char *arg)
2790{
2791 disable_apic_timer = 1;
2792 return 0;
2793}
2794early_param("noapictimer", parse_disable_apic_timer);
2795
2796static int __init parse_nolapic_timer(char *arg)
2797{
2798 disable_apic_timer = 1;
2799 return 0;
2800}
2801early_param("nolapic_timer", parse_nolapic_timer);
2802
2803static int __init apic_set_verbosity(char *arg)
2804{
2805 if (!arg) {
2806 if (IS_ENABLED(CONFIG_X86_32))
2807 return -EINVAL;
2808
2809 ioapic_is_disabled = false;
2810 return 0;
2811 }
2812
2813 if (strcmp("debug", arg) == 0)
2814 apic_verbosity = APIC_DEBUG;
2815 else if (strcmp("verbose", arg) == 0)
2816 apic_verbosity = APIC_VERBOSE;
2817#ifdef CONFIG_X86_64
2818 else {
2819 pr_warn("APIC Verbosity level %s not recognised"
2820 " use apic=verbose or apic=debug\n", arg);
2821 return -EINVAL;
2822 }
2823#endif
2824
2825 return 0;
2826}
2827early_param("apic", apic_set_verbosity);
2828
2829static int __init lapic_insert_resource(void)
2830{
2831 if (!apic_mmio_base)
2832 return -1;
2833
2834 /* Put local APIC into the resource map. */
2835 lapic_resource.start = apic_mmio_base;
2836 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2837 insert_resource(&iomem_resource, &lapic_resource);
2838
2839 return 0;
2840}
2841
2842/*
2843 * need call insert after e820__reserve_resources()
2844 * that is using request_resource
2845 */
2846late_initcall(lapic_insert_resource);
2847
2848static int __init apic_set_disabled_cpu_apicid(char *arg)
2849{
2850 if (!arg || !get_option(&arg, &disabled_cpu_apicid))
2851 return -EINVAL;
2852
2853 return 0;
2854}
2855early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid);
2856
2857static int __init apic_set_extnmi(char *arg)
2858{
2859 if (!arg)
2860 return -EINVAL;
2861
2862 if (!strncmp("all", arg, 3))
2863 apic_extnmi = APIC_EXTNMI_ALL;
2864 else if (!strncmp("none", arg, 4))
2865 apic_extnmi = APIC_EXTNMI_NONE;
2866 else if (!strncmp("bsp", arg, 3))
2867 apic_extnmi = APIC_EXTNMI_BSP;
2868 else {
2869 pr_warn("Unknown external NMI delivery mode `%s' ignored\n", arg);
2870 return -EINVAL;
2871 }
2872
2873 return 0;
2874}
2875early_param("apic_extnmi", apic_set_extnmi);